Answer:
Below
Explanation:
The two angles labeled are alternate angles of a pair of parallel lines crossed by a transversal ( the diagonal) ....so they are equal
x+ 18 = 4x+15 Solve for x
3 = 3x ====> x = 1
Now....x+18 angle and angle ABD are complementary....the add to 90 °
so x+18 + ABD = 90° x = 1 from above....so
1 + 18 + ABD = 90
19 + ABD = 90
ABD = 71 °