This picture depicts a right triangle. When using a right triangle to find a certain side, you must use the pythagorean theorem which is a^2 + b^2 = c^2 a and b are the legs and c the hypoteneuse Plug in the numbers and solve 5^2 + 12^2 = c^2 25 + 144 = c^2 169 = c^2 Now square root both sides Answer is x= 13
