Question

Which is an equation of a circle with center (2, 7) and radius 4? (x - 7)2 + (y - 2)2 = 16 (x - 2)2 + (y - 7)2 = 4 (x – 2)2 + (y - 7)2 = 16 (x + 2)2 + (y + 7)2 = 4

Answer 1

Third choice

Explanation:

The standard form of a circle is

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

where h and k are coordinates of the center and r is the radius squared. We have h = 2, k = 7, and r = 4 (we will have to square it to fit it into the equation properly). Filling in accordingly:

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

The third choice is the one you want.