Thread: 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

Originally Posted by topaz192

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

There are several ways, the one I favor most is this:

The two y values are equal, so let them be equal:




.

Now use x = -8 in either one of the original equations:


So the solution is (x, y) = (-8, -17).

-Dan