Your answer is D.
Will always be x2 and y2 starting off
<em><u>Question:</u></em>
<em>Mrs. Magdalino kept records on how much she spent on gasoline and the maintenance of her car. She found that it cost $485 to drive 500 mi in a month.</em>
<em>a) Find the cost per mile. Write an equation that relates the cost c for gasoline and maintenance of a car to the number of miles m the car is driven.</em>
<em>b) Use the equation to find the cost for driving 1200 miles.</em>
<em>c) About how many miles are driven for a cost of $820?</em>
<em><u>Answer:</u></em>
a)
$485/500mi = <u><em>$0.97/mi</em></u>
c = cost
m = miles driven
cost per miles driven = cost / mile driven = <u><em>c/m</em></u>
b)
(1200 mi)*($0.97/mi) = <u><em>$1164</em></u>
c)
(x miles)*($0.97/mi) = $820
*divide both sides by $0.97/mi
x miles = $820/($0.97/mi)
<u><em>x = 845.36 miles</em></u>
First you solve for y.
5x+ y= 12 so Y= 12-5x
And plug it into the next equation
3x- 3(12-5x) = 18
Distribute
3x-36+15x=18
Add 36 to both sides
3x+ 15x= 54
18x= 54 ... divide
x= 3
And you can plug in x to solve for Y
5(3) + y = 12
15+ y = 12 ...subtract 15 from both sides
y= -3
V= 1/3 pi r^2h
Find the radius
r=d/2
r=8/2
r= 4
V= 1/3 pi (4)^2•6
V=32pi or 100.53
-4 because when you did use 12 divided by 3 you get four but this is negative so you get a negative answer
