A circle is shown. A secant goes through the center point and intersects a tangent at a point outside of the circle. The length of the tangent is 7 inches. The length of the external part of the secant is 4 inches.
Kylie writes an equation to solve for the diameter, d, of the circle shown. Solve Kylie’s equation to find the diameter of the circle.

4 (d + 4) = 72

What is the diameter?

7.5 in.
8.25 in.
11.25 in.
13.25 in.