Answer to Question #196294 in Trigonometry for niamh

Question

A, B & C form the vertices of a triangle.

∠

 CAB = 90°, ∠

 ABC = 74° and AB = 8.9.

Calculate the length of BC rounded to 3 SF.

Answer 1

In triangle BAC

$\angle A=90^o\\ \angle B=74^o\\$

And AB= 8.9

So

$Cos(74^o)=\frac{AB}{BC}$

$0.27=\frac{8.9}{BC}$

BC=32.9