Question 768969
n1 + n2 = 90
n1 + 50 + 3n1 = 90
4n1 + 50 = 90
4n1 = 90 - 50
4n1 = 40
4n1 / 4 = 40 / 4
n1 = 10 degrees ans.

n2 = 50 + 3(10)
n2 = 80 degrees ans.

checking:

n1 + n2 = 90
10 + 80= 90