Question

Suppose a triangle has sides a, b, and c, and that a2 + b2 < c2. Let be the measure of the angle opposite the side of length c. Which of the following must be true? Check all that apply.

A. The triangle is not a right triangle.
B. The triangle is a right triangle.
C. cos < 0
D. is an acute angle.

Answer 1

if the triangle is right angled then c^2 = a^2 + b^2 but that is not the case.