**Guide :High School **

# Prove the following theorem indirectly. We will give you a start.. . Prove that a triangle cannot have two right angles.. A triangle cannot have two right

Prove the following theorem indirectly. We will give you a start.. . Prove that a triangle cannot have two right angles.. A triangle cannot have two right angles. Suppose a triangle had two right angl**Suppose a triangle had two right angles.The sum of all angles of any triangle is 180°.The measure of a right angle is 90°.By difference, the measure of the other angle can be determined.Since the two angles have a measure of 90° each, then by difference, the measure of the third angle is 180° - (90° + 90°) = 0°.If the angle is 0°, there would only be two sides.A triangle has three sides.Therefore, a triangle can't have two right angles.**...