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Plz someone help I'm not getting it one but. The options for both of the x' s are -5,-4,-3,-2,-1,1,2,3,4,5 and I have to choose one for each, but I am not getting it correct, so plz help if u can

Plz someone help I'm not getting it one but. The options for both of the x' s are-example-1
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4x + 5y = 7....multiply by 3
3x - 2y = -12 ...multiply by -4
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12x + 15y = 21 (result of multiplying by 3)
-12x + 8y = 48 (result of multiplying by -4)
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0x + 23y = 69....and as u can see, the x's have opposite coefficients, which cancels them out
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and if u want the y's to have opposite coefficients...
4x + 5y = 7.....multiply by 2
3x - 2y = -12 ...multiply by 5
and the y's will cancel out...because one will be 10y and the other will be -10y


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