9514 1404 393
Answer:
∠GDH = ∠GHD = 50°
Explanation:
Angles FGD and EDG are alternate interior angles, so are congruent. That means angle EDG is 100°. The angle sum theorem tells us ...
∠EDG = ∠EDH +∠HDG
100° = 50° +∠HDG
50° = ∠HDG
You can find the measure of ∠DHG a couple of different ways. It is an alternate interior angle congruent to ∠EDH, so is 50°. It is one of two remote interior angles that have a sum equal to the exterior angle FGD, so is ...
∠DHG = ∠FGD -∠HDG = 100° -50° = 50°
So, angles DHG and HGD both have measures of 50°. When a triangle has two angles with the same measure, it is an isosceles triangle.