Geometry
posted by Ryan on .
A circle with the equation (x + 3)2 + (y  2)2 = 25 is reflected over the line x = 2.
What is the equation of the image?

y does not change
x new = (2x) + 2 = 4x
x = 4xnew
(4xnew + 3)^2  (y2)^2 = 25
(xnew +7)^2  (y2)^2 = 25
same as
(xnew7)^2  (y2)^2 = 25
check
old center was at x = 3
that is 5 to the left of x = 2 line
5 to the right of the line is x = 7
sure enough