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4 years ago

Solve the system of equations x+4y=15 2x-y=-15

Mathematics

1 answer:

Lady_Fox [76]4 years ago

7 0

x+4y=15 2x-y=-15

We have to make x neg.

-2(x) + 4y (-2)= -2(15)

-2x-8y=-30

2x-y=-15

-9y= -45

Solve for y

Y=-45/-9

Y = 5

Substitute your y answer into one original equation to find x .

x+4y=15

X+4(5)=15

X+20=15

X=15-20

X= -5

Answer is (-5,5)

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