Question

Hi, can someone help me figure out how to do this question?

A 5m stepladder propped against a classroom wall forms an angel of 30 degrees with the wall. Exactly how far is the top of the ladder from the floor? Express your answer in radical form.

This chapter right now that we're doing is related to special angles of trig ratios. How would I write the formula using that?

Anyways, the answer at the back says

5 square root 3
---------------
2

Thanks in advance

Answer 1

Cos 30 = A/H
Cos30 = A/5
*switch A and Cos30*
A=5(Cos30)
A=5•sqrt of 3
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2
*Remember, Cos30 is equal to A/H which is sqrt3/5