In the figure below, suppose m∠2 = 51° and m∠3 = 96°. Complete the statements below. The sum of the...

In the figure below, suppose m∠2 = 51° and m∠3 = 96°.
Complete the statements below.
The sum of the interior angle measures of a triangle must be [].
So, m∠2 + m∠3 + m∠4 = [].
We are given that m∠2 = 51°.
So, m∠3 + m∠4 = [].
From the figure, we can see that m∠1 + m∠2 = [].
Since m∠2 = 51°, it must be that m∠1 = [].
Therefore, m∠1 [] m∠3 + m∠4.
This result is an example of the Exterior Angle Property of Triangles.
For any triangle, the measure of an exterior angle