Question

For the graph x = -3 find the slope of a line that is parallel to it.

Answer 1

the ilne paralell to x=something is x=something else (both are constants)

slope=rise/run

x=-3
it rises infiniley and runs 0 (goes left to right 0)
slope=infinity/0=undefined

the slope is undefined
paralell lines have same slope
so the slope of a paralell line is also undefined

Answer 2

a parallel line has the same slope and the slope intercept form is Y=mx+b x being the slope so that would be y=-3m+b so a parallel lines slope would also be -3.