Question 489954
16z -9 + 4z + 3 = 90
20z - 6  = 90
20z = 96
z = 4.8

16(4.8) - 9 = 67.8 degrees
4(4.8) + 3 = 22.2 degrees
67.8 degrees + 22.2 degrees = 90 degrees.
Cleomenius.