Respuesta :

Answer:

4.2 ft

Step-by-step explanation:

Reference angle = 77°

Opposite side = DE = x

Hypotenuse = CD = 4.3 ft

Apply the trigonometric function of sine. Thus:

Sin 77 = opp/hyp

Sin 77 = x/4.3

Multiply both sides by 4.3

4.3 × sin 77 = x

x = 4.2 ft (nearest tenth)