Math

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Can someone please help with this problem?
Solve by the elimination method.
7r-9s= -58
9r+7s=74
I know that I need to multiply the first equation by 9 and the second equation by 7.
The equations look like this:
63r-81s= -522
63r+49s=518
After this I get confused. Could someone please help?
Thanks.

  • Math -

    subtract

    0r-130s=-1040

  • Math -

    But how would I solve for r?
    s=8 does that mean r=0?
    Thanks.

  • Math -

    Never mind I got the answer for r.
    Thanks.

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