Answer:
x = 16, y = 20
Step-by-step explanation:
7x + 4 + 5x - 16 = 180
7x + 5x + 4 - 16 = 180
12x - 12 = 180
12x / 12 - 12 / 12 = 180 / 12
x - 1 = 15
x = 15 + 1
x = 16
5x - 16 + 6y - 4 = 180
5x + 6y - 16 - 4 = 180
5x + 6y - 20 = 180
5x + 6y = 180 + 20
5x + 6y = 200
Substitute x = 16,
5 ( 16 ) + 6y = 200
80 + 6y = 200
6y = 200 - 80
6y = 120
y = 120 / 6
y = 20
