Question

In ΔDEF, the measure of ∠F=90°, DE = 70 feet, and EF = 57 feet. Find the measure of ∠D to the nearest tenth of a degree.

Answer 1

54.5°

Explanation:

You know that in a right triangle, the sine of an angle is given by ...

Sin = Opposite/Hypotenuse

sin(D) = EF/ED = 57/70

The inverse sine function is used to find the angle:

∠D = arcsin(57/70)

∠D ≈ 54.5°