Question

What is the error in this problem

Answer 1

The error is the use of wrong trigonometric ratio formula.

Sine was used instead of tangent.

It should be:
`tan(A) = (36)/(84)`

Explanation:

Side length, 36, is opposite to <A. Side length, 84, is the adjacent side. Therefore, the right trigonometric ratio formula to use is:

`tan(A) = (opposite)/(adjacent)`

`tan(A) = (36)/(84)`

`A = tan^(-1)((36)/(84))`

m<A ≈ 23°

The error made was the use of wrong trigonometric ratio formula.