Answer:
10
Step-by-step explanation:
x-9+0=1
x-9=1
x=1+9
x=10
the third one, y = 1/2x + 3
One is 19 and one is 37
rise / run = slope
13 + 13 / - 5 + 8 = 26 / 3 = 8.666 or 8 and 2 / 3