How do you solve the following system?: $3x+3y= -7 , 3x − y = 30$

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Answer 1 · 2017-02-01T09:34:20

$y=-9 1/4, x=6 11/12$

$3x+3y=-7 -------1$

$3x-y=30--------2$

$4y=-37$ ---------------------------------- $1-2$

$y=-37/4$

$y=-9 1/4$

substitute $y= -37/4$ in-------2

$3x-(-37/4)=30$

$3x+37/4=30$

$3x=30-37/4$

$3x=120/4-37/4$

$3x=83/4$

multiply both sides by 4

$12x=83$

$x=83/12$

$x=6 11/12$

substitute $y=-37/4, x= 83/12$ in-------2

$3(83/12)-(-37/4)=30$

$249/12+37/4=30/1$

$(249+111=360)/12$

$249/12+111/12=360/12$

$360/12=360/12$

How do you solve the following system?: 3x+3y= -7 , 3x − y = 30 3x+3y= -7 , 3x − y = 30