Question

Which expression shows the length, BC, of the base of the stand?
9 cot 70°
9 cos 70°

Answer 1

9 cot 70..............

Answer 2

Option A, 9 cot 70°

Explanation:

ΔABC is a right angle triangle in which AC = 9 in

∠ ABC = 70°

and we have to find the length of BC ( base of the stand )

tan 70° =
`(height)/(base) =(AC)/(BC)`

BC =
`(AC)/(tan70)`

BC = 9 cot 70° [
`(1)/(tan70*)` = cot 70° ]

Option A, 9 cot 70° is the answer.