Solve the system by the substitution method.
y=-4x-8
2x-3y=10
Give the solution set.

I tried the obvious 2x-3(-4x-8)=10 But it hasn't gotten me anywhere, I've been working on this for a long time now though so i'm probably overlooking something easy. Any help?

Question

Solve the system by the substitution method.
y=-4x-8
2x-3y=10
Give the solution set.


I tried the obvious 2x-3(-4x-8)=10 But it hasn't gotten me anywhere, I've been working on this for a long time now though so i'm probably overlooking something easy. Any help?

campbell_st · Answer

made a typo 

so if y = -4x - 8

then substituting


2x -3(-4x - 8) = 10

2x + 12x + 24 = 10

solve for x

then substitute into y = -4x - 8

to find y

campbell_st · Answer

the equation in x you need to solve is

14x + 24 = 10

subtract 24 from both sides

14x = -14

x = -1

anonymous · Answer

Ah! Totally makes sense, I got to that point before but in my frustration -14 divided by 14 = 0. Who knows what I was thinking. Thank you!!