Answer:
Length of the drain pipe is 72.15 feet.
Step-by-step explanation:
From the figure attached,
A drain pipe is to be laid between two pints P and Q.
Point P is 15 ft higher than the other point Q.
Angle of elevation of point P from point Q is 12°.
Let the length of pipe is l feet.
By applying Sine rule in the given right triangle PRQ,
Sin(∠Q) = [tex]\frac{\text{Opposite side}}{\text{Adjacent side}}[/tex]
Sin(12) = [tex]\frac{\text{PR}}{\text{PQ}}[/tex]
0.20791 = [tex]\frac{15}{l}[/tex]
[tex]l=\frac{15}{0.20791}[/tex]
[tex]l=72.146[/tex]
l = 72.15 ft
Therefore, length of the drain pipe is 72.15 feet.