I've been stuck on this problem for a long time now. Any help would be super appreciated!
What is the measure of $\angle D$?
Express your answer in degrees rounded to the nearest whole degree.
Let angle D be x. If 2 sides of a triangle are congruent, then 2 of the angles are also congruent. Therefore, we can label the triangle like this:
For the rightmost triangle, we can set up an equation:
\(5x+5x+90-4x=180\)
Can you take it from there?
Thank you so much! I got it!
Use the WHOLE triangle in the diagram
x + 5x + 90 = 180 solve for x
+7 
