Question

through:(5,0), parallel to y=4/5x-3

Answer 1

If you are looking for a line: remember point-slope form.
In this question you have a point (5,0) and you can get the slope from the equation. Since parallel lines have the same slope you can just use 4/5.
Just plug the numbers into the equation: y-y1=m(x-x1)
y-0=4/5(x-5)
Therefore y=4/5x-4

Answer 2

To be parallel lines both must have the same slope.  Our reference line is:

y=0.8x-3 so the slope is 0.8, given the point (5,0) we can solve for the y-intercept, or "b" of y=mx+b for our parallel line.

0=0.8(5)+b

0=4+b

b=-4 so

y=0.8x-4  is the parallel line to y=0.8x-3 that passes through (5,0)