Ok, i was just on a site for tutoring but it isn't making much sense to me!

What steps do i follow through when doing this?

y=3x+7

y=x-9

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- Mar 9th 2008, 08:34 PMtopaz192How do you do system of equations?
Ok, i was just on a site for tutoring but it isn't making much sense to me!

What steps do i follow through when doing this?

y=3x+7

y=x-9 - Mar 9th 2008, 08:38 PMtopher0805
To solve it, set the two expressions equal to each other.

$\displaystyle 3x+7 = x-9$

Then solve for x, to get:

$\displaystyle x=-8$ - Mar 9th 2008, 08:45 PMtopaz192
ok, so on one like

y=2x+3

y=3x+1

itll be 2x + 3=3x+1?

and solve from there? aren't you suppose to change signs when bringing it over? - Mar 9th 2008, 08:53 PMtopher0805
Switch signs? Sort of, let me give you a step by step version of this:

$\displaystyle 2x+3=3x+1$

Subtract 1 from both sides:

$\displaystyle 2x+2=3x$

Subtract 2x from both sides:

$\displaystyle

2=1x$

So:

$\displaystyle x=2$

Do you see? - Mar 9th 2008, 09:02 PMtopaz192
I think so.

So on one like

y=2x-10

y=4x-8

itll be 2x-10 = 4x-8

2x=-2

x=-1?

ha i suck at combining like terms and what not lol. - Mar 9th 2008, 09:14 PMtopher0805
Yeah, it looks like you've got it now.

- Mar 9th 2008, 09:17 PMtopaz192
Yay! Thanks for your time! = ]

- Mar 10th 2008, 04:55 AMtopsquark