Question

Find Measure of angle B (m18. a = 7 m, b = 5 m, m∠A = 45°

Answer 1

30.34 degree

Explanation:

Apply sine formula

`(sin\left(A\right))/(a)=(sin\left(B\right))/(b)`

`(\sin \left(45^(\circ \:)\right))/(7)=(\sin \left(b\right))/(5)`

->simplify

`(\sin \left(b\right))/(5)=((√(2))/(2))/(7)`

you will get

`\sin \left(b\right)=(5√(2))/(14)`

which
sin b is about 0.50507

`sin^(-1)\left(0.50507\right)`

->arc sine in degree mode

the answer is 30.34