Use slopes and y-intercepts to determine if the lines y=5x+5 and 5x-y=-5 are parallel.

Answer: They are not parallel, they are coincident

Step-by-step explanation:

If two lines have the same slope but a different y-intercept, the lines are parallel. If two lines have the same slope and the same y-intercept, the lines are coincident.

We can rewrite 5x-y=-5 adding - 5x to both sides and multiplying by - 1:

5x - y = -5

5x - y - 5x = - 5 - 5x (adding - 5x to both sides)

-y = - 5 - 5x

Multiplying by - 1

y = 5x + 5

Both equations look the same so they are coincident. They have the same intercept y=5 and the same slope m=5.