for the first one your going to use a table of x on one side and y on another and put 0 for x and y for 1 then subsitute it into the question like so. 3(0)+3y=12 then 3 times 0 is 0, next divide 3 to each side so it's 12÷3 then you'll get 4 so y=4 the do the same for x. then graph it so take a pint from the question then do rise over run. for example (2,4) graph that then go up by 3 then over 4.
the next question get the question in slope intercept form y=mx+b so take 3y away from each side then take 2x from each side so it should look like -3y=-2x- 9 then graph it cause -2 is slope so the y Inter. is 9 then that should be it.