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stellarik [79]
4 years ago
15

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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