Question

Solving for equations by substitution .
15) 6x+6y=-6
5x +y = -13
My answers Please check!
6x+6y=-6
y=-5x-13
6x + 6(-5x -13) = -6
6x -30x -78 =-6
-24x-78+78 = -6+78
-24x=-72
-2x/-24= -72/-24
x= 3.25
6(3.25)+6y=-6
19.5+6y = -6
-19.5 -19.5
6y=-25.5
6y/6=-25.5/6
y = -4.25

Answer 1

That seems like the right answers

Answer 2

That 2 should be a 24 lol

Answer 3

And just so you know a good way to check is plugging the answers into one of the original equations and seeing if it works

Answer 4

I know lol. just need to check with others.

Answer 5

no right answer is x = -3 and y=2

Answer 6

Thank you! Can you show me where I went wrong.?

Answer 7

-24x-78+78 = -6+78
it should be in this step -24x - 78 = -6

Answer 8

why did you repeat 78 again it totally changed the equation

Answer 9

to isolate -24x
and if you added the same amount on the right-hand side the equation remains the same

Answer 10

I put it like that to show that I was moving it over to the other side of the equal sign

Answer 11

but you dont need to remove it you just have a remaining last step which is -24x=-6 +78 .... x=-3

Answer 12

your division is the incorrect part
you can check if you did it correctly by using the values of x and y into any of the two original equations