SOLUTION: 2x+7y=8 5x-3y=21 por los tres metodos please

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Question 334462: 2x+7y=8
5x-3y=21
por los tres metodos please

Answer by mananth(16946)   (Show Source): You can put this solution on YOUR website!
2x+7y=8..........1
5x-3y=21 ........2
..
multiply equation 1 by -5 and equation 2 by 2 and add them
-10x-35y+10x-6y=-40+42
-41y=+2
y=-2/41
..
plug value of x in equation 1
2x +7(-2/41)= 8
2x= 8+(14/41)
2x=328+14/41
divide by 2
y= 342/ 41*2
y=171/7

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