How do you solve the following system: 4x+y=-7, 2x + 3y = 8 4x+y=−7,2x+3y=8?

1 Answer
1s2s2p
Apr 25, 2018

(-2.9,4.6)(−2.9,4.6)

Explanation:

Rearrange the second equation to get:
2x=8-3y2x=8−3y

Also:
2(2x)+y=-72(2x)+y=−7
2(8-3y)+y=-72(8−3y)+y=−7
16-6y+y=-716−6y+y=−7
-5y=-23−5y=−23
y=23/5=4.6y=235=4.6

Now we put this in:
4x+23/5=-74x+235=−7
4x=-7-23/5=(-35-23)/5=-58/54x=−7−235=−35−235=−585
x=-58/20=-2.9x=−5820=−2.9

(-2.9,4.6)(−2.9,4.6)

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