Question

Solve the equation by using substitution.
x+5y=3
3x-2y=-8

Answer 1

Do you know how you would start this, or are you lost already?

Answer 2

lost already

Answer 3

Alright, no problem. Firstly, you'll need to solve for a variable. For simplicity, I'd choose the x in the top equation. Or, if you'd like, pick another. Either way, pick one. We're going to solve for it.

Answer 4

Ok x is fine so then we would have to get x on one side so would it be x=-5y+3 ?

Answer 5

Yes! So, now you have "x=-5y+3", and "3x-2y=-8". Now you'll need to literally substitute the given formula that equals x in the first equation in for the x of the second. If you're following what I mean, rewrite the new second equation as it would appear exactly one step ahead of now.

Answer 6

3(-5y+3)-2y=-8

Answer 7

Correct! Now, using PEMDAS, what's your next step? (Tell me if you reach a point where you understand what you have to do from that point, and I'll check your answer)

Answer 8

-15y+9-2Y=-8

-17y+9=-8

17y=-17

y=-1

Answer 9

Almost completely correct, but you made one minor error: in the third step, the negative on the "17y" disappeared. It should still be there.

Answer 10

oops so y=1

Answer 11

yep. There ya go!

Answer 12

Perfect thank you!

Answer 13

You're most welcome!