Question

Sharma is building a shed and wants to determine the measurements for the roof. The span of the roof will be 10 feet and she plans to use a 5:12 roof pitch. This means that the roof will rise 5 inches for every 12 horizontal inches. Complete her diagram by determining the unknown angle measures, to the nearest degree, and side lengths, to the nearest tenth of a foot.

Answer 1

Answer:

In the figure below :

d = 2.08, e = 5, c = 5.42 , a = 22.78°, b = 67.22°

Step-by-step explanation:

Side lengths :

$2\cdot e=10\\ \Rightarrow e=5 feet\\\frac{d}{e}=\frac{5}{12}\\\Rightarrow d=\frac{25}{12}\approx 2.08 feet$

By pythagoras theorem,

$c^2=d^2+e^2\\c^2=29.33\\c\approx 5.42 feet$

Now to find angles,

$a+b+90^{\circ}=180^{\circ}\\\Rightarrow a+b=90^{\circ}\\\tan a=\frac{d}{e}\\\Rightarrow \tan a =0.42\\\Rightarrow a=22.78^{\circ}\\\Rightarrow b=67.22^{\circ}$