Respuesta :

< BAC = 50
< BCA = 90

interior angles of a triangle add up to 180

so < ABC = 180 - (90 + 50) = 180 - 140 = 40

and < ABC = < CDE.......so < CDE = 40 <===

The answer would be  because if angle BAC= 50 degrees then angle DCE= 50 degrees. These triangles are the same. Each triangle has to equal 180 degrees. We know that this is a 90 degree triangle.
50, 90 is what we have so far and we need angle CDE. 50+90= 140
140+what=180
140+40=180 so the answer is 
Angle CDE=40 degrees