You can put this solution on YOUR website! So if you rewrite the equation in slope intercept form which is y=mx+b you get
y=-3x+7
which means the intercept is (0,7) so you plot that point
and the slope is -3, which is -3/1 so from (0,7) you go 3 points DOWN and 1 point to the RIGHT. That will be your second point :)