Question

What is an equation of a circle with center (2,7) and radius 4?

Answer 1

Equation of a circle:

(x - h)^2 + (y - k)^2 = r^2

In this case:

center (2,7) and radius 4 so h = 2, k = 7 and r = 4

Equation:

(x - 2)^2 + (y - 7)^2 = 4^2

(x - 2)^2 + (y - 7)^2 = 16

Hope it helps.