Answer:
Step-by-step explanation:
y = 3x + 9
3y - 9x = 12 Add 9x to both sides
3y = 9x + 12 Divide by 3
y = 9/3 x + 12/3
y = 3x + 4
Since the slopes are the same for both equations and since the y intercept of the first one is 9 and the second one is 4 (the y intercepts are different), the lines are parallel.
