What are the unknown side lengths and angles of the given triangle?

g.r

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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.
attachment.php


So i have a good understanding of using sin cos and tan but I'm completely lost when it comes to this question. I understand e = 5 but i don't really get the 5:12 roof pitch, or how to solve for d. Once i have d, i can use it to apply the pythagorean theorem to get c, and then find the angles right?
2e = 10
d / e = 5 / 12d
d^2 + e^2 = c^2
tan a = d / e
a + b = 90 degrees
 
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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.
attachment.php


So i have a good understanding of using sin cos and tan but I'm completely lost when it comes to this question. I understand e = 5 but i don't really get the 5:12 roof pitch, or how to solve for d. Once i have d, i can use it to apply the pythagorean theorem to get c, and then find the angles right?
2e = 10
d / e = 5 / 12d
d^2 + e^2 = c^2
tan a = d / e
a + b = 90 degrees

You need to label you values. What is a? b, c, d, e? From the equations some can be guessed at but that
d / e = 5 / 12d
sort of messes things up. Did you mean
d / e = 5 / 12?
If so, it looks like you just have to work through the numbers: I would go about it by finding a with that and your formula
tan(a) = d/e = 5/12
so that
a = tan-1(5/12)
You also have
d= (5/12) e
etc. as you indicated
 
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