Question 184549
First, graph the intercept, when x=0, y=-3.
{{{ drawing( 300, 300, -10, 10, -10, 10, grid(1), circle(0,-3,.4)) }}}
.
.
.
Next use the slope. 
The slope is the number of units of rise (y) for each unit of run (x) for your line.

So for every positive 1 step in x, you take a positive 4/5 step in y.
More practically, for every 5 positive steps in x, you take 4 positive steps in y.
.
.
. 
Start at (0,-3), 5 steps in x and 4 steps in y would then take you to another point (0+5,-3+4)=(5,1)
.
.
.
Graph that point and connect the line through those points. 
{{{ drawing( 300, 300, -10, 10, -10, 10, grid(1), circle(0,-3,.4), circle(5,1,.4),graph( 300, 300, -10, 10, -10, 10, (4/5)x-3)) }}}