Answer: 9 inches. Do the pythagorean theorem to find your answer. Formula: a^2 + b^2 = c2 12 = b 15 = c a^2 + 12^2 = 15^2 Simplify the equation a^2 + 144 = 225 Subtract 144 on both sides. a^2 = 81 Square root of 81 is 9.
The answer is c because of the fact that if the 2 angles at 55 and 20 that means that you have to add them together and get to 180 for the triangle to be true
