I had $3.00.
My Mom gave me $10.00.
My Dad Gave me $30.00.
My Aunt & Uncle gave me $100.00.
I had another $7.00.
How much did I have?

Answers

Answer 1

Respuesta:

200.00.

Exli con i

esunsua ma

Answer 2

Here, I required to determine how much I have.

According to the data in the question;

I had $3.00.Then, My Mom gave me $10.00.Then, My Dad gave me $30.00.My Aunt & Uncle gave me $100.00.I had another $7.00.

Therefore, the algebraic sum of all my money results in the amount I have now.

The amount I have now is:

$3.00 + $10.00 + $30.00 + $100.00 + $7.00= $150.

The amount I have now is: $150


Related Questions

Area= 7 1/4 x 11 2/3

Answers

Answer:

Area=84.5833333333

Step-by-step explanation:

Answer:

Step-by-step explanation:

To make this easy, convert them both into improper fractions.

Multiply 7x4= 28 + 1 = 29/4

Multiply 11 x 2 = 22 +3= 25/2

29/4 x 25/2 = 725/8

simplified it is 90 5/8

Hope this helps :)

Riley worked 5 1/4 hours on Monday 3 3/8 hours on Tuesday and 2 5/6 hours on Wednesday he rounded the hours to five 3 and 2 before adding them together to get 10 hours did he make a high or low estimate​

Answers

Answer:

Low estimate

Step-by-step explanation:

2 5/6 rounded is 3 so the total would be 11 hours if everything is rounded.

Answer:

The answer is low

What is the answer please help you can change my life.

Answers

Answer:

The side length is irrational

Step-by-step explanation:

Because the square root of 23 or 20+3 is a non-perfect square root and it's a never ending decimal.

Circle B is shown. Line segments C B, D B, and E B are radii and they form 3 congruent angles. What does Arc C D E describe? a minor arc a major arc a semicircle a chord

Answers

Answer:

a major arc

Step-by-step explanation:

A circle is the locus of  point in which has a given distance from a fixed point (center of the circle).

B is the center of the circle C B, D B, and E B are radii forming 3 congruent angle. Since the sum of angles in a circle is 360°, the 3 line segments form 3 congruent angles of 120° each (360/3).

Therefore the angle measure of Arc C D E =  Arc CD + Arc DE = 120° + 120° = 240°

A major arc is an arc greater than a semicircle (> 180°). This means that Arc C D E is a major arc

Answer:

a major arc

Step-by-step explanation:

a major arc

a major arc

a major arc

a major arc

a major arc

a major arc

a major arc

what’s -14 = -2(2x+2)

Answers

X = 4 is your answer

Identify a pattern in each lists of numbers. Then use this pattern to find the next number. 17,13,9,5,1

Answers

Answer:

-5 -9 -13....

Step-by-step explanation:

17-4=13 so you basically minus 3 each time.

Which equation has no solution?

Answers

Answer:

B) -6 (w - 4) + 8w = 2 (w + 9) has no solution

Step-by-step explanation:

The total cost C (in dollars) of playing an online game is given by the literal equation C = 30x + 50, where x is the number of months you play the game. Solve the equation for x. How many months do you play the game when you spend $170? $260?

Answers

Answer:

4 months and 7 months

Step-by-step explanation:

C = 30x + 50

C is cost so when we spend $170 we can solve for x.

$170 = 30x + 50

170 - 50 = 30x + 50 - 50

170 - 50 = 30x

120 = 30x

120/30 = 30x/30

120/30 = x

4 = x

So he has played 4 months when he spends $170

C is cost so when we spend $260 we can solve for x.

$260 = 30x + 50

260 - 50 = 30x + 50 - 50

260 - 50 = 30x

210 = 30x

210/30 = 30x/30

210/30 = x

7 = x

So he has played 7 months when he spends $260

The enrollment in fall 1993 was 14.3 million. If you were to use the model of 1993 what would the enrollment be?

Answers

Answer:

Why is college important? It’s a question you may have heard among friends, or perhaps you’ve even wondered yourself about the benefits of earning a degree. And it’s a good question to be asking as you consider your future—and everything that will include, from earnings potential to starting or switching your career. Here are five facts you should know as you consider the value of a college education.

1. People with college degrees earn more on average.

According to averages calculated by the US Bureau of Labor Statistics (BLS), people with a bachelor’s degree earn around 64% more per week than individuals with a high school diploma, and around 40% more than those with an associate’s degree. Those with an associate’s degree earn around 17% more than those with a high school diploma.

Over the course of a year (52 weeks), those percentage differences add up. For example, if you compare the average median annual earnings for those with a bachelor’s degree to those with a high school diploma, you’ll discover a difference of almost $24,000 per year in income.

2. College can help you expand your network.

Salary is far from the only answer for why is college important. You may have heard this before, but who you know and who your friends know is important. No matter how talented you are, a strong network can help you start and advance in your career.

At an Art Institutes school, you’ll not only have the chance to connect with instructors* who have worked in their fields, but you can also meet students in a variety of creative fields. These diverse connections may well benefit you in the future. Plus, you can also participate in professional groups, community activities, and industry conferences where you can grow your circle even more. Your Career Services department may also connect you with alumni in your field and can continue to provide networking support after graduation!

3. Gaining new skills can help enhance your current career.

Building your skill set and industry knowledge can help you move forward in your current career, and the skills you learn go beyond the obvious. At The Art Institutes, not only can you build your technical and artistic skills, but you can also develop your critical thinking, communication, and teamwork.

Earning your degree can demonstrate to a current employer that you’re serious about your career, and that you’re prepared to take on bigger projects and more responsibility. In the long term, when you apply to new jobs in your field, having a degree can provide you with a competitive edge. Even if the job doesn’t require a degree, your education—along with the quality of your work—may help you stand out among applica

Step-by-step explanation:

{7, 8, 9, 10} {9, 10, 11, 12} Which of the following shows the intersection of the sets? A. {9, 10} B. {7, 8, 9, 10} C. {9, 10, 11, 12} D. {7, 8, 9, 10, 11, 12}

Answers

Answer:

{ 9 , 10 }

Option A is the correct option.

Step-by-step explanation:

Let the sets be A and B

A = { 7 , 8 , 9 , 10 }

B = { 9 , 10 , 11 , 12 }

The intersection of sets A and B is the set of all ements which belongs to both A and B.

The intersection of sets A and N is denoted by ( A ∩ B ) and read as A intersection B.

A ∩ B = { 7 , 8 , 9 , 10 } { 9 , 10 , 11 , 11 , 12 }

Now, list the elements which are present in both sets. A ∩ B = { 9 , 10 }

Hope I helped!

Best regards!

Answer:

its a

Step-by-step explanation:

30 pts + brainliest to best answer

Answers

Answer:

D) 7 1/5

Step-by-step explanation:

2 2/5 is equivalent to 12/5 then if you divide it by 1/3 you will get 7 1/5 or 7.2

After a 65% reduction you purchase a new washing machine on sale for $196. What was the original price of the washing machine

Answers

Answer:

$323.40

Step-by-step explanation:

A ball is thrown into the air. Its height (in feet) t seconds later is given by h(t)=64t−16t^2 a) What is the height of the ball 1 second after it has been thrown? b) After how many seconds does the ball hit the ground? c) At what time(s) is the ball 30 feet above the ground?

Answers

Answer:

A) 48 feet

B) 4 seconds

C) 0.54 seconds and 3.46 seconds

Step-by-step explanation:

So we have the function:

[tex]h(t)=64t-16t^2[/tex]

Which represents the height h(t) of the ball after t seconds.

A)

To find the height of the ball 1 second after it has been thrown, substitute 1 for t. Thus:

[tex]h(1)=64(1)-16(1)^2[/tex]

Simplify:

[tex]h(1)=64-16[/tex]

Subtract:

[tex]h(1)=48[/tex]

So, after 1 second, the height of the ball is 48 feet above the ground.

B)

To find out how many seconds after being thrown does the ball hit the ground, we'll set h(t) to 0. 0 means that it will be 0 feet above ground level: in other words, on the ground. So:

[tex]0=64t-16t^2[/tex]

Solve for t. Factor out a 16t:

[tex]0=16t(4-t)[/tex]

Zero Product Property:

[tex]16t=0\text{ or } 4-t=0[/tex]

Solve for t:

[tex]t=0\text{ or } t=4[/tex]

We'll ignore the first zero. So, the ball lands after 4 seconds of being thrown into the air.

C)

To find out at what time(s) the ball is 30 feet above the ground, set h(t) to 30 and solve for t:

[tex]30=64t-16t^2[/tex]

First, divide everything by 2 to simplify things:

[tex]15=32t-8t^2[/tex]

Subtract 15 from both sides:

[tex]-8t^2+32t-15=0[/tex]

Now, to find the zeros, we can use the quadratic formula. a is -8, b is 32, and c is -15. Thus:

[tex]x=\frac{-b\pm\sqrt{b^2-4ac}}{2a}[/tex]

Substitute:

[tex]x=\frac{-32\pm\sqrt{32^2-4(-8)(-15)}}{2(-8)}[/tex]

Simplify:

[tex]x=\frac{32\pm\sqrt{544}}{16}[/tex]

Use a calculator. Approximate:

[tex]x\approx0.5422\text{ or } x\approx 3.4577[/tex]

So, the ball is 30 feet above the ground after 0.54 seconds and 3.46 seconds.

And we're done :)

-8=x+11/2 please help me

Answers

Answer:

Hey there!

-8=x+11/2

-16/2=x+11/2

-27/2=x

Let me know if this helps :)

Answer:  -27/2     or        -27

Step-by-step explanation:

You didn't use parentheses so the equation isn't clear.  

I answered for both possibilities.

                  [tex]-8=x+\dfrac{11}{2}\\\\\\-8-\dfrac{11}{2}=x\\\\\\-\dfrac{16}{2}-\dfrac{11}{2}=x\\\\\\\large\boxed{-\dfrac{27}{2}=x}[/tex]

                                                    [tex]-8=\dfrac{x+11}{2}\\\\\\-8(2)=\dfrac{x+11}{2}(2)\\\\\\-16=x+11\\\\\\-16-11=x\\\\\\\large\boxed{-27=x}[/tex]

Jeremy Sullivan delivers newspapers for the Dispatch. He receives 14.20 per
paper, 6 days a week (for the daily paper), and 500 for the Sunday paper. He
delivers 124 daily papers each day and 151 Sunday papers each week. What is
his total pay for the week?

Answers

Answer:

Total earnings per week

=18114.8¢

Step-by-step explanation:

He receives 14.20¢ per paper, 6 days a week.

He receives 50¢ for the Sunday paper.

He delivers

124 daily papers each day

He earns= 124*14.20*6

He earns=10564.8¢

151 Sunday papers each week.

He earns= 151*50

He earns= 7550¢

Total earnings per week

=10564.8+7550

=18114.8¢

Is pi rational?? helppppp

Answers

Answer:

Yes

Step-by-step explanation:

Pi is a rational number, because it goes on forever.

How do you do letter b?

Answers

Answer:   175

Step-by-step explanation:

[tex]g(35)= \int\limits^{35}_0 {f(x)} \, dx =\int\limits^{30}_0 {f(x)} \, dx +\int\limits^{35}_{30} {f(x)} \, dx[/tex]

                            =     137.5   +      37.5

                            =  175

           

Answer:

g(35) = 137.5

Step-by-step explanation:

g(35) = g(30) + [g(35) - g(30)]

g(35) = 100 + 5(15)/2

g(35) = 137.5

Which of the following is an example of stratified sampling when obtaining a sample of 100 high school students? A. Choosing 100 students at random from a specific grade level at a high school.B. Choosing 100 students sitting in one random section of the cafeteria at a high school.C. Choosing 25 students at random from each of four different grade levels at a high school.D. Choosing 100 students at random from a high school. E. Choosing 100 students at random from an AP Statistics class at a high school.

Answers

Answer:

Option C - Choosing 25 students at random from each of four different grade levels at a high school

Step-by-step explanation:

For us to achieve the conditions for a stratified random sample, the target population must be split into different groups which in this case, it's grade levels.

Looking at the 5 options given in the question, Options A, B, D and E are random but they are not truly stratified in their sampling approach. This is because the sample population must be selected at random from each of these groups and it's only option C which is choosing 25 students from each of four different grade levels or groups that reflects that.

Let u = (−2, 3, 1), v = (−1, −1, 2), and 3u − 2v − 4w = (3, 2, −3). Find: a. The vector w.b. -2u + 3v - 5w

Answers

Answer:

(a) w = [tex](\frac{-7}{4} , \frac{9}{4}, \frac{1}{2})[/tex]

(b) -2u + 3v - 5w = ([tex]\frac{39}{4}[/tex], [tex]\frac{-54}{4}[/tex], [tex]\frac{3}{2}[/tex])

Step-by-step explanation:

Given:

u = (−2, 3, 1)

=> u = -2i + 3j + k                           --------------------------(i)

v = (−1, −1, 2)

=> v = -i - j + 2k                                --------------------(ii)

3u − 2v − 4w = (3, 2, −3)

=> 3u − 2v − 4w = 3i + 2j - 3k             ------------------(iii)

(A) TO FIND THE VECTOR w

Let:

w = (a, b, c) = ai + bj + ck

(a) Substitute u, v and w into equation (iii)

3u − 2v − 4w = 3i + 2j - 3k

3(-2i + 3j + k) - 2(-i - j + 2k) - 4(ai + bj + ck) = 3i + 2j - 3k

(b) Solve the equation in step (a) by opening the brackets and collecting like terms

(-6i + 9j + 3k) - (-2i - 2j + 4k) - (4ai + 4bj + 4ck) = 3i + 2j - 3k

open brackets

-6i + 9j + 3k + 2i + 2j - 4k - 4ai - 4bj - 4ck = 3i + 2j - 3k

collect like terms

-6i + 2i - 4ai + 9j + 2j - 4bj + 3k - 4k - 4ck = 3i + 2j - 3k

i(-4 - 4a) + j(11 - 4b) + k(-1 - 4c) = 3i + 2j - 3k

(c) Solve for a, b and c in step (b)

Comparing both sides of the equation, we have;

-4 - 4a = 3              ----------(*)

11 - 4b = 2              -----------(**)

-1 - 4c = -3             ------------(***)

From (*)

4a = -4 - 3

4a = -7

a = [tex]\frac{-7}{4}[/tex]

From (**)

4b = 11 - 2

4b = 9

b = [tex]\frac{9}{4}[/tex]

From (***)

-1 - 4c = -3

4c = -1 + 3

4c = 2

c = [tex]\frac{2}{4}[/tex]

c = [tex]\frac{1}{2}[/tex]

Remember that

w = (a, b, c)

w = ai + bj + ck

Therefore,

w = [tex](\frac{-7}{4} , \frac{9}{4}, \frac{1}{2})[/tex]

(B) TO FIND -2u + 3v - 5w

Remember that;

u = (−2, 3, 1)

v = (−1, −1, 2),

w = [tex](\frac{-7}{4} , \frac{9}{4}, \frac{1}{2})[/tex]

Substitute u, v, w into the expression as follows;

-2(−2, 3, 1) + 3(−1, −1, 2) - 5[tex](\frac{-7}{4} , \frac{9}{4}, \frac{1}{2})[/tex]

Expand

(4, -6, -2) + (−3, −3, 6) - [tex](\frac{-35}{4} , \frac{45}{4}, \frac{5}{2})[/tex]

Collect like terms

(4-3+[tex]\frac{35}{4}[/tex], -6-3-[tex]\frac{45}{4}[/tex], -2+6-[tex]\frac{5}{2}[/tex])

Solve

([tex]\frac{39}{4}[/tex], [tex]\frac{-54}{4}[/tex], [tex]\frac{3}{2}[/tex])

Therefore, -2u + 3v - 5w = ([tex]\frac{39}{4}[/tex], [tex]\frac{-54}{4}[/tex], [tex]\frac{3}{2}[/tex])

Find an equation of the line having the given slope and containing the given point. m=-5 (5,7)

Answers

Answer:

y = -5x + 32

Step-by-step explanation:

Slope-Intercept Form: y = mx + b

Step 1: Write in known variables

slope m = -5

y = -5x + b

Step 2: Find b

7 = -5(5) + b

7 = -25 + b

b = 32

Step 3: Write linear equation

y = -5x + 32

Answer:

y - 7 = -5(x - 5)

Step-by-step explanation:

Pre-Solving

We are given that a line has a slope of -5 and contains the point (5,7).

We want to write the equation of this line.

The equation of this line can be written in three ways:

Point-slope form, which is [tex]y-y_1=m(x-x_1)[/tex], where m is the slope and [tex](x_1,y_1)[/tex] is a point.Standard form, which is ax+by=c, where a, b, and c are free integer coefficients. Slope-intercept form, which is y=mx+b, where m is the slope and b is the value of y at the y intercept.

Either one of these ways works, but let's use point-slope form, as that form is the easiest.

Solving

We can immediately substitute the values into the formula to get the equation.

We can start with the slope; replace m with -5 in the formula.

[tex]y-y_1=m(x-x_1)[/tex] => [tex]y-y_1=-5(x-x_1)[/tex]

Now, we can replace [tex]x_1[/tex] and [tex]y_1[/tex] with 5 and 7 respectively to get:

y - 7 = -5(x - 5)

the value of the function f(x)=6x + 3 at 4 is

Answers

solution

Answer:

here we go 6×4+3

now 24+3

hence the answer is

27 ans

Answer:

x = -2

Step-by-step explanation:

f(x) = 6 x + 3×4

f(x) = 6 x + 12

6 (x + 2) = f(x)

x = -2

Hope I helped! Please label me as Brainliest!

In 9 days a group of workers can plant 54 acres what’s there rate in acres per day

Answers

Answer:

Step-by-step explanation:

9 3/4 acres in 3 3/8 days = 9 6/8 acres in 3 3/8 days

(72 + 6)/8 = 78/8

(24 + 3)/8 = 27/8

78/8 divided by 27/8 = 78/27 = 26/9 or 2 8/9 acres/day

Answer:

6 acres per day

Explanation:

Because you want to narrow it down to 1 day, you divide the total amount of acres by the total days. 54/9=6, meaning they plant 6 acres each day.

tyler says that Figure B is a scaled copy of Figure A because all of the peaks are half as tall.

Answers

Answer:

No

Step-by-step explanation:

For the smaller figure to be a scaled copy, the figure would have to be half as wide as well,

On Sunday, the temperature dropped 24° in 6 hours. What was the average change in temperature per hour?​

Answers

Answer:

The temperature drops 4° every hour

Step-by-step explanation:

Step 1:

24° ÷ 6

Step 2:

24 : 6 = 4 : 1

Answer:

4

Hope This Helps :)

Answer:

[tex]\boxed {\tt -4 \textdegree \ per \ hour }[/tex]

Step-by-step explanation:

This question asks us to find the average rate of change in temperature per hour.

Therefore, we must divide the temperature change by the hours.

[tex]rate \ of \ change =\frac{temperature \ change}{hours}[/tex]

The temperature dropped 24 degrees in 6 hours. Since it dropped, the change was negative.

[tex]temperature \ change = -24 \textdegree \\hours = 6 \ hours[/tex]

Substitute the values into the formula.

[tex]rate \ of \ change =\frac{-24 \textdegree}{6 \ hours}[/tex]

Divide.

[tex]rate \ of \ change = - 4 \textdegree / hour[/tex]

The average change in temperature was -4° per hour. The temperature dropped 4 degrees each hour.

A total of 6.2 percent of the prime time viewing audience watched shows on ABC, 8.1 percent watched shows on CBS, 7.4 percent on Fox, 6.4 percent on NBC, 3.1 percent on Warner Brothers, and 2.8 percent on UPN. A total of 66 percent of the audience watched shows on other cable networks, such as CNN and ESPN.
What will be the prime time viewing percentage of the pie chart for the following data? (Only consider the viewers watching non-cable news.) (Round your answers to 2 decimal places.)

Answers

Answer:

For each one it is shown below

Step-by-step explanation:

The computation of the prime time viewing percentage for the following data is shown below:l;

but before that we need do the total which is

= 6.2% + 8.1% + 7.4% + 6.4% + 3.1% + 2.8%

= 34%

Now for each one the viewing percentage is

For ABC

[tex]= \frac{6.2}{34}[/tex]

= 18.24%

For CBS

[tex]= \frac{8.1}{34}[/tex]

= 23.82%

For NBC

[tex]= \frac{6.4}{34}[/tex]

= 18.82%

For Warner brothers

[tex]= \frac{3.1}{34}[/tex]

= 9.12%

For fox

[tex]= \frac{7.4}{34}[/tex]

= 21.76%

For UPN

[tex]= \frac{2.8}{34}[/tex]

= 8.24%

The relative growth rate for a certain type of bacteria population is 85% per hour. A small culture has formed and in just 2 hours the count shows to be 12,500 bacteria in the culture. What is the initial number of bacteria in the culture?

Answers

Initial number =p=3662

Answer:

3663 bacteria

Step-by-step explanation:

solve for x: -2x - 4 > 8

Answers

Steps to solve:

-2x - 4 > 8

~Add 4 to both sides

-2x > 12

~Divide -2 to both sides

x < -6

Best of Luck!

two poles 8m and 13m high
are placed opposite to each other across a 12
metre long road find the distance
between their tops

Answers

Answer:

13 m

Step-by-step explanation:

The distance x is:

x = √12² + (13 -8)² = √144 + 25 = √169 = 13 m

HELLLLLPPPPPPP PLZZZZZZ HELP A$AP PLZZZZZZZZZ I WILL MARK BRAINLEST

Answers

Answer:

$430

Step-by-step explanation:

Step 1:

300 - 50

Step 2:

350 + 20

Step 2:

370 + 60

Answer:

$430

Hope This Helps :)

describe the correct error a student made when solving the equation 4=-2(x-3) what is the correc scolution?

Answers

Answer:

x =1

Step-by-step explanation: Correct solution

[tex]4=-2(x-3) \\\\\mathrm{Switch\:sides}\\-2\left(x-3\right)=4\\\\\mathrm{Divide\:both\:sides\:by\:}-2\\\frac{-2\left(x-3\right)}{-2}=\frac{4}{-2}\\\\Simplify\\x-3=-2\\x-3+3=-2+3\\\\Simplify\\x = 1[/tex]

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crusaders return to Europe from the Middle East was good that Europeans wanted so.... What were the American colonists of the eighteenth century protesting against? the French and Indian War mercantilism new taxes in which they had no say An artist makes a scale drawing of a parallelogram-shaped sculpture. The scale is 10 cm on the drawing for every 8 meters on the sculpture. What is the area of the scale drawing? Show your work. change them into either active or passive form of voice depending on the nature of the sentence number dog chased the girl para que sirven los principales planos de las historietas If fx = 3x over 5 +3 which of the following is the inverse A box contains four tiles 1,4,5 and 8 as shown. Kelly chooses one time places it back in the box then chooses a second tile. What is the probability that the sum of the two chosen tiles is greater than 7? Simplify 200xyz3 . Which of the following statements best describes literacy rates in north Africa Determine the standard form of the equation of the line that passes through (-2, 0) and (-8, 5).5x + 6y = 105x - y = - 106x + 5y = - 10d. 5x + y = -10C.b.Please select the best answer from the choices providedABD McCoy Brothers manufactures and sells two products, A and Z in the ratio of 5:2. Product A sells for $86; Z sells for $124. Variable costs for product A are $45; for Z $49. Fixed costs are $429,500. Compute the contribution margin per composite unit. What is the solution to the equation 1 + 3x = -13 + 5x? Convert your answer to a decimal, if necessary. What charge do protons have in an atom? What is the maximum number of covalent bonds that an oxygen atom with atomic number 8 can make with hydrogen? How is Twain effective at using humor? Cite evidence of humorous moments in the text. Also consider Twains intent and viewpoint in your response. Solve for xX + 2w = m I will give the brainiest Venetta buys 2 pounds of pistachios and 3 pounds of almonds. The pistachios cost $4 moreper pound than the almonds. She pays a total of $48. Select all the correct statements aboutthis situation.A.One pound of pistachios plus 1 pound of almonds cost $20.B.Reducing the number of pounds of almonds by one results in a total cost of $40.C.The pistachios cost twice as much per pound as the almonds.D.The costa, in dollars of 1 pound of almonds is modeled as 2(a - 4) + 3a = 48.E.The cost p, in dollars, of 1 pound of pistachios is modeled as 2p + 3(p - 4) = 48. Tag groups can be nested up to ____ levels deep, with up to _______ tag subgroups under a single parent. Why do many historians consider theBoston Tea Party as part of the AmericanRevolution?A. Mohawk Indians served in the Continental ArmyB. It was an act of defiance against the King of EnglandC. Over 100 British soldiers were killed during this event Find the equation of the sphere centered at (-9,9, -9) with radius 5. Normalize your equations so that the coefficient of x2 is 1. -0.Give an equation which describes the intersection of this sphere with the plane z = 0.