Work Step by Step
We are given two lines written in the form $y=mx+b$, where m is the slope of the line and the point (0,b) is the y-intercept. $y=5x+8$ and $y=5x-8$ We know that m=5 for both lines, so both lines have the same slope. Also, b=8 for one line and b=-8 for the other, so the lines must have different y-intercepts. For non-vertical lines, two lines are parallel if they have the same slope and different y-intercepts, so these lines must be parallel.