Answer:
x=7
y=9
Step-by-step explanation:
x+7y=70 ...(1)
3x-6y=-33
divide by 3
x-2y=-11 ...(2)
(1)-(2) gives
x+7y-x+2y=70+11
9y=81
y=9
x-2*9=-11
or x=-11+18=7
C. $122.10
20 first hour
20+0.1*20 = 22 second hour
22+0.1*22 = 24.2 third hour
24.2+0.1*24.2 = 26.62 fourth hour
26.62+0.1*26.62 = 29.282 fifth hour
Total=$122.10
Let y = the distance between the top left corner and the bottom right corner
y^2 = 24^2 + 15^2
y^2 = 801
y = 3 * sqrt(89)
Now we can find x.
12^2 + x^2 = (3 * sqrt(89))^2
x^2 = 657
x = 3 * sqrt(73) or 25.63
we can see that the center is (-3, 3) and the radius is 9 units.
<h3 /><h3>
How to find the center and radius of the circle?</h3>
The general circle equation, for a circle with a center (a, b) and radius R is given by:
(x - a)^2 + (y - b)^2 = R^2
Here we have the equation:
x^2 + y^2 + 6x = 6y + 63
Let's complete squares:
x^2 + y^2 + 6x - 6y = 63
(x^2 + 6x) + (y^2 - 6y) = 63
(x^2 + 2*3x) + (y^2 - 2*3y) = 63
Now we can add and subtract 9, (two times) so we get:
(x^2 + 2*3x + 9) - 9 + (x^2 - 2*3x + 9) - 9 = 63
(x + 3)^2 + (y - 3)^2 = 63 + 9 + 9 = 81 = 9^2
(x + 3)^2 + (y - 3)^2 = 9^2
Comparing with the general circle equation, we can see that the center is (-3, 3) and the radius is 9 units.
If you want to learn more about circles:
brainly.com/question/1559324
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