See picture for math work and answer.
Since these are similar triangles you can use any two corresponding sides to figure out the scale factor.
Use the bottom side. Going from the first triangle to the second the scale factor is:
15/9 = 5/3
Write the equation of the circle with center (3, 2) and radius r = 7. Use the ^ key for the exponents. Write your answer as the example:
(x - 4)^2+(y+8)^2=25
3.2x-9.6=-.4x+1.2
3.2x=-.4x+10.8
3.6x=10.8
X= 3
