If you were to use the substitution method to solve the following system, choose the new equation after the expression equivalent to x from the second equation is substituted into the first equation.

2x – 3y = –29
x + 4y = 13

Question

If you were to use the substitution method to solve the following system, choose the new equation after the expression equivalent to x from the second equation is substituted into the first equation. 

2x – 3y = –29 
x + 4y = 13

blurbendy · Answer

so we need x to equal something in the second equation.  how would we do that?

anonymous · Answer

multiply the second equation by 2?

blurbendy · Answer

no, this isn't like the elimination method, so we don't have to worry about that.  right now we have:
x + 4y = 13

how do we get x by itself?

blurbendy · Answer

we need x by itself so we can substitute into the first equation

anonymous · Answer

so we are substituting?

blurbendy · Answer

yup, that's what the question is telling us to do

blurbendy · Answer

did you get it?

anonymous · Answer

not yet

blurbendy · Answer

for the second equation, just get x by itself on the left side.  that means you need to move +4y to the right side

anonymous · Answer

so would my answer be 2(–4y + 13) – 3y = –29

blurbendy · Answer

i dont know what your answer choices are, but if that's one of them, then that's right

otherwise, you might have to simplify it a little

anonymous · Answer

okay thanks! i got it correct!

blurbendy · Answer

cool.  yw