y = 10x - 30
Step-by-step explanation:
x = 5
5 x 10 = 50
50 - 30 = 20
y = 20
x = 6
6 x 10 = 60
60 - 30 = 30
y = 30
x = 7
7 x 10 = 70
70 - 30 = 40
y = 40
x = 8
8 x 10 = 80
80 - 30 = 50
y = 50