Question

2x+3y=1 and y=-2 - 9 solve using linear combination method. Please explain steps.

Answer 1

`x=17`

Explanation:

`2x+3y=1`

`y=-2-9`

• In order to combine these two equations, an idea you need to keep in mind is finding a way of setting these equations as equal to each other. I saw that each equation shared a common value,
  `y`. In this case, we need to isolate
  `y` in the first equation so that both equations
  `=y`.

`2x+3y=1`

`3y=-2x+1`

`(3y)/(3)=(-2x+1)/(3)`

`y=-(2)/(3)x+(1)/(3)`

• With this, we now know that both
  `-2-9` and
  `-(2)/(3)x+(1)/(3)` are equal to
  `y`, so we can set them equal to each other.

`y=-(2)/(3)x+(1)/(3)`

`y=-11`

`-(2)/(3)x+(1)/(3)=-11`

• Reply to this if anything I'm saying or doing is confusing in any way, or if you find a mistake. :) Solve for
  `x`.

`-(2)/(3)x+(1)/(3)=-11`

`-(2)/(3)x=-11-(1)/(3)`

`-(2)/(3)x =-(33)/(3)-(1)/(3)`

`-(2)/(3)x =-(34)/(3)`

`-(2)/(3)x(-(3)/(2))=-(34)/(3)(-(3)/(2))`

`x=(102)/(6)=17`

`x=17`

• Hopefully this answer is correct AND makes sense in terms of how I achieved it. Again, reply to this with any questions or mistakes I made and I'll do my best to answer or fix them.