Question

1) Solve for Side A

2) Solve for Angle B

Answer 1

1) 42.51

2) 39.76

Answer 2

solution given;

let

AB=a

AC=b=30ft

AB=c=20ft

<A=115°

By using Cosine rule.

a²=b²+c²-2bc cos angle

a²=30²+20²-2*30*20 Cos 115°

a²=1807.1419

a=√[1807.1419]

a=42.51

Side A is 42.51ft.

Again

Cos B=
`(a²+c²-b²)/(2ac)`

Cos B=
`(42.51²+20²-30²)/(2*42.51*20)`

Cos B=0.7687

<B=Cos -¹(0.7687)

<B=39.46°

Angle B is 39.46