Answer:
18
Step-by-step explanation:
x^2 + y^2 – 14x + 10y = 250
x^2 -14x + y^2 + 10y = 250
x^2 - 14x + (-7)^2 + y^2 + 10y + (5)^2 = 250 + (-7)^2 + (5)^2
(x-7)^2 + (y + 5)^2 = 250 + 49 + 25
(x-7)^2 + (y + 5)^2 = 324
Comparing with the general circle (x - b)^2 + (y - a)^2 = r^2
we have; r^2 = 324
r = square root(324)
r = 18
