hi there.
if it's easier for you to graph in slope-intercept form, you can easily change it.
5x - 10y = 20 (subtract 5x on both sides)
10y = 5x - 20 (divide all numbers by 10)
(5 divided by 10 is 0.5) (-20 divided by 10 is -2)
y = 1/2x - 2
now just graph it using this new equation. start at (0, 0) and go down by 2 points. this lands you on (0, -2). from that point, go up 1 point and 2 points to the right. this lands you on (2, -1) then connect the two dots with a line.
hope this helps!