Hi, We know:
Sin(a + b) = 2.Sin(a).Sin(b)
Then,
= 2Sin(a).Cos(b)/Cos(a).Cos(b)
Canceling Cos(b)
= 2Sin(a)/Cos(a)
As Tan(a) = Sin(a)/Cos(a)
Then we will stay:
= 2Tan(a)
Or
= Tan(a) + Tan(a)
There is anything wrong on the alternatives
The answer to your question is 1,293,182
8/ Sine 50 = n/ Sine 90
8 sine 90 = n Sine 50
8 sine 90 / sine 50 = n
n = 10.4
You solve this by plugging one equation into the other. Usually you have to rewrite one equation to make this work. In this case I choose to rewrite y-4x=0 as y=4x.
After plugging it into the second, you get:
3x + 6*4x = 9 => 27x = 9 => x=1/3
Putting this solution back into y=4x gives us y=4/3