Question

L is parallel to y=5x. Write an equation for line L in point-slope form

Answer 1

point slope is y - Y=m(x-X) where m is slope and (X,Y) is a given point on the line

so you can get y-Y= 5(x-X)
and then just choose a point for your parallel line to go through, say (2,3)

so you get y-3 = 5(x-2)