Answer:
CD = 51.6 feet (to nearest tenth of a foot)
Explanation:
Check the diagram of the triangle in the attachment below.
From the right angled triangle shown, CD is the hypotenuse and DE is the opposite side to ∠C. To get the length CD, we will use the SOH, CAH, TOA trigonometry identity.
According to SOH;
Sin∠C = opp/hyp = DE/CD
Given ∠C = 81° and DE = 51feet
Sin81° = 51/CD
CD = 51/Sin81°
CD = 51.63572feet
CD = 51.6 (to nearest tenth of a foot)