A circle is shown. Secant A D and tangent E D intersect at point D outside of the circle. Secant A D intersects the circle at point B. The length of A B is a, the length of B D is 10, and the length of D E is 12.
Which equation results from applying the secant and tangent segment theorem to the figure?
12(a + 12) = 102
10 + 12 = a2
10(a + 10) = 122
10(12) = a2