Substitute 0 for y and then solve for x. Then plot the point (a,0) where a is the value you just calculated for x when y is zero.
Substitute 0 for x and then solve for y. Then plot the point (0,b) where b is the value you just calculated for y when x is zero.
Note: Graphing this equation by using the intercepts is a very poor strategy for this particular linear equation. In fact, it is a poor strategy for any linear equation of the form because both intercepts are the same point, namely the origin. Therefore, plotting the intercepts results in plotting only one point which does not specify a particular line.
For this equation, either plot the origin and then use the slope to find another point on the line, or you can just select a value for x different than zero and calculate the resulting y value to get a second point on the line.
John
My calculator said it, I believe it, that settles it