Question

How do I solve this system using substitution?
In steps please? :)

x + 12y = 68
x + 8y - 12

Answer 1

where the = in second equation?

Answer 2

Assuming the second equation should be x + 8y = 12...here's what I would do:

subtract 8y from each side in eq 2
x = 12 - 8y
Then substitute "12 - 8y" into the first equation for x
12 - 8y +12y = 68
Solve for y, then use that result in the original second equation to find x

Answer 3

Sorry. It's x = 8y - 12

Answer 4

No problem...then it is already in form to substitute. use "8y - 12" where I said "12 - 8y"

Answer 5

So for 12 - 8y +12y = 68 , do I add 12 on the other side?

Answer 6

oh wait do i combine 8y + 12y?

Answer 7

it is -8y + 12y = 4y so your equation would simplify to 12 + 4y = 68 Then you would subtract 12 from each side to get 4y=56 then to find y just divide both sides by 4 which gives you y=14

Now that you have y you can substitute it in to solve for x. x=8y-12 so x=8(14)-12 which goes to x=112-12 which trivial math gives you x=100

so your solution to your system is (100,14)

Answer 8

Where did you get 4 ?