Question

I need someone to check my answer please!

Write an indirect proof proving the two non-right angles of a right triangle measure less than 90°.

Answer 1

Let's assume that the two non-right angles of a right triangle do not measure less than 90 degrees.

A right angle measures 90 degrees. If two angles form a right triangle, then they must measure less than 90 degrees, but add up to the sum of 90. If the angles do not measure less than 90 degrees, but instead measure at least 90 degrees, then the triangle is not a right triangle.

Therefore, the two angles of the triangle measure less than 90 degrees.

Answer 2

@Hero @perl

Answer 3

@amistre64