Given that AE is a tangent of the circle with the center at B, BC = 3.5, and AE = 24, which is the length of EC?

7

13

25

49

We are actually given here a right triangle where EC is the hypotenuse. The length of one side is AE = 24, and the other side AC is simply twice BC, so AC = 7:

EC^2 = AE^2 + AC^2

EC^2 = 24^2 + 7^2

EC = 25