Under a dilation, triangle XYZ where X(4, 7), Y(-3, 8), and Z(-2, -1) becomes triangle X’Y’Z’ where X’(12, 21), Y’(-9, 24), and
-BARSIC- [3]
It is 3, the points are all 3 times greater
We can say that:
8x = -2ax
8 = -2a
a = -4
22y = - 2by
22 = -2b
b = -11
37 = a² + b² - r²
37 = (-4)² + (-11)² - r²
r² = 16 + 121 - 37
r² = 100
r = 10
With all this information, we can say that:
The center of the circle is: (-4 ; -11)
and the radius of the circle is r = 10
P.S:
(a - x)² + (b-y)² = r²
a² - 2ax + x² + b² -2by + y² - r² = 0
x² + y² -2ax - 2by + a² + b² - r² = 0
