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-7x + 6y = -8
6x + 12y = 24
Use the substiution method

User SanguineL
by
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1 Answer

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Answer:

(1,2)

Explanation:

Solve the system of linear equations via substitution:


-7x+6y=-8


6x+12y=24


6x+12y=24

Subtract 12y on both sides


6x=24-12y

Divide EVERYTHING by 6


x=4-2y

DO NOT forget this equation. We will use this at the end!

Now we need to plug in our x equation into one of the two equations. Lets do the 1st one and solve for y.


-7(4-2y)+6y=-8

Distribute -7


-28+14y+6y=-8

Combine like terms


-28+20y=-8

Subtract -28 on both sides


20y=20

Divide by 20


y=1

We have our y value, so remember the equation we just plugged in? Plug this value into that equation.


x=4-2(1)

Multiply


x=4-2

Subtract


x=2

The solution to the system of linear equations is (1,2)

User Hector Magana
by
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