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2 years ago

-2x + 6y = 6 -7x + 8y = -5

Mathematics

1 answer:

AleksandrR [38]2 years ago

4 0

Answer:

$x=-2\\y=2$

Step-by-step explanation:

$-2x+6y=6\\-7x+8y=-5$

Let's multiply the first equation by 7 and the second equation by -2

$(7)(-2x+6y=6)\\(-2)(-7x+8y=-5)$

$-14x+42y=42\\14x-16y=10$

Now add them together. In this step, x is eliminated.

$26y=52$

Divide by 26.

$y=\frac{52}{26}\\ y=2$

Now plug this into any of the two equations to find x.

$-2x+6y=6\\-2x+6(2)=6\\-2x+12=16\\-2x=16-12\\-2x=4\\x=\frac{4}{-2}\\ x=-2$

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