Question

a radio station has a broadcast area in the shape of a circle with equation x^2+y^2=5 625

Answer 1

let us assume that the center of the circle is (0,0)

(x-h)² + (y-k)² = r²
x² + y² = 5,625

r² = 5,625
r = √5,625
r = 75

Area of a circle = π * r²
A = 3.14 * (75mi)²
A = 3.14 * 5,625 mi²
A = 17,662.50 mi²