AB = 12
OB = 3.5
OA = 12.5
Let
a = 12
b = 3.5
c = 12.5
The legs are 'a' and 'b'. The hypotenuse is c
If the triangle was a right triangle, then a^2+b^2 = c^2 would be true. Let's find out
a^2 + b^2 = c^2
12^2 + 3.5^2 = 12.5^2
144 + 12.25 = 156.25
156.25 = 156.25
Since we get a true equation at the end, this means a^2+b^2 = c^2 is also true when (a,b,c) = (12,3.5,12.5)
Therefore, angle B is a 90 degree angle so AB is a tangent to the circle.
Answer: Choice C) Yes; 12^2+3.5^2 = 12.5^2