Answer:
m∠D = m∠E = 80°
Explanation:
You want the measures of the angle of elevation (∠E) from A to B and the angle of depression (∠D) from B to A when they are described by the expressions 7x-4 and 4(x+8), respectively.
Angles
The angle of elevation and the angle of depression between the same two points have the same measures.
m∠E = m∠D
7x -4 = 4(x +8)
7x -4 = 4x +32
3x = 36 . . . . . . . . add 4-4x to both sides
x = 12 . . . . . . . . divide by 3
4(x +8) = 4(20) = 80 . . . . . . . . find the angle measures
Each of the angles has a measure of 80°.