Question 220760
(1) 8x -y=20
(2) -5x +y =-8
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(1)+(2) 3x +12
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x=4,,,,,,,subst  in  (1) 
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8(4) -y =20
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-y = 20-32= -12
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y =12
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checking,,,(4, 12),,,,(1) 8(4) -(12) =20,,,,,,ok
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(2) -5(4) +(12) =-8,,,,-20 +12 =-8,,,,ok   
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