solve -2x+6y=6

-7x+8y=-5

solve -2x+6y=6

-7x+8y=-5

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Middletown, CT

Hi Kristen;

-2x+6y=6

-7x+8y=-5

Let's select one equation and isolate one variable.

I randomly select the first equation and randomly select the variable x.

-2x+6y=6

Let's subtract 6y from both sides...

Let's subtract 6y from both sides...

-6y+-2x+6y=-6y+6

-2x=-6y+6

Let's divide both sides by -2...

(-2x)/-2=(-6y+6)/-2

x=3y-3

Let's take the second equation and substitute x with 3y-3...

-7x+8y=-5

[(-7)(3y-3)]+8y=-5

(-21y+21)+8y=-5

-21y+21+8y=-5

-13y+21=-5

Let's subtract 21 from both sides...

-21-13y+21=-5-21

-13y=-26

Let's divide both sides by -13...

(-13y)/-13=-26/-13

A negative number divided by a negative number has a positive result...

Let's plug this into either equation to establish the value of x...

I randomly select the first equation...

-2x+6y=6

-2x+[(6)(2)]=6

-2x+12=6

Let's subtract 12 from both sides...

-12-2x+12=6-12

-2x=-6

Let's divide both sides by -2...

(-2x)/-2=-6/-2

Let's verify our results by plugging both values into the second equation...

-7x+8y=-5

[(-7)(3)]+[(8)(2)]=-5

-21+16=-5

-5=-5

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