I need help with this
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Using a trigonometric relation we will see that:
1) DE = 33.86
2) R = 20.6°.
1) We want to get DE which is the adjacent cathetus to the given angle.
Then we can use the trigonometric relation:
tan(a) = (opposite cathetus)/(adjacent cathetus).
Here we have:
a = 21°
opposite cathetus = 13
adjacent cathetus = DE.
Replacing that we get:
DE = 13/tan(21°) = 33.86
2) Now we want to get an angle.
This time we have:
Using the same trigonometric relation we get:
tan(R) = 9/24
Using the inverse tangent function:
R = Atan(9/24) = 20.6°.
If you want to learn more about right triangles:
https://brainly.com/question/2217700
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