15 points to answer these two questions?

1) how can graphing methods be used to solge a system of linear equations and how can you determine the equations of the two lines by analyzing the graph?

2) solve this system of equations and explain what method you used to find your solution.
8x-y=-9
4x-3y=-22

Manny bought 12 pounds of vegetables at the supermarket. 75% of the vegetables were on sale. how many pounds of vegetables were not on sale? 98 points : )

Isuck at math ; ^; m a student solved this problem and said the answer is 3 feet. chase had a roll of ribbon that contained 7 7/8  feet of ribbon. he cut off one piece that was 3 5/8  feet long and another piece that was 1 1/4  feet from the roll. how much ribbon was left on the roll? is the student's answer reasonable? yes, the answer is reasonable. no, the answer is not reasonable. it should be about 2 feet. no, the answer is not reasonable. it should be about 13 feet. no, the answer is not reasonable. it should be about 4 feet.

X^2/100+y^2/25=1 the y-intercepts are at: a) (-10,0) and (10,0) b) (0,10) and (0,5) c) (0,-5) and (0,5)