Question

please answer this question fast

Answer 1

I'll solve on paper
there you go

Answer 2

sin ( a + 2 b) = √3/2
a + 2 b = 60° ------------ equation 1
cos ( a + 4 b) = 0°
a + 4 b = 90° ------------ equation 2
subtracting equation 1 and 2 we get :
- 2b = - 30°
b = 15 °
putting the value of b in equation 1 we get :
a + 2 * 15 = 60
a + 30 = 60
a = 30 °