Name: Joe Who is asking: Student Level: Secondary Question: whats the answer to this question? 3x+y=11 x+2y=-3 its substitution method i am having alot of trouble figuring it out. send the answer as soon as possible. thank you Hi Joe, I see two reasonable choices here. Solve the first equation for y and substitute into the second equation. Solve the second equation for x and substitute into the first equation. There are two other choices, solve the first equation for x and substitute into the second or solve the second equation for y and substitute into the first. Both of these choices lead immediately to fractions so I would chose one of ther first two. I don't think either is easier than the other so I am going to select the first choice. Solve the first equation for y. 3x + y = 11 thus 3x + y -3x = 11 - 3x or y = 11 - 3x Substitute into the second equation. x + 2y = -3 thus x + 2(11 - 3x) = -3 x + 22 - 6x = -3 -5x = -25 Thus x = 5 Finally substitute x = 5 into either of the equations you started with to find y. Now try it the other way. Solve the second equation for x and substitute into the first equation. You should find the same answer. Cheers, Penny Go to Math Central