Answer:
85
Step-by-step explanation:
think about the diagonal of the frame, breaking up a rectangle into 2 right angled triangles. we are already given the legs of the triangle (77, and 36) and now we have to solve fro the hypotenuse (or the diagonal). so use pythagorean theorem :
77^2 + 36^2 = c^2
7225 = c^2
c = 85
