Question

What is the diameter of the circle given by the equation (x + 7)2 + (y + 2)2 = 121?

A.
22
B.
33
C.
11
D.
5.5

Answer 1

A.

22

Explanation:

The equation of the circle is written in the form

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

So

(x + 7)2 + (y + 2)2 = 11^2

The radius is 11

The diameter is twice the radius, so the diameter is 2*11 =22