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Solving systems of equations by substitution

Solving systems of equations by substitution-example-1
User Lamarr
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Equation 1) 2x - 3y = -1
Equation 2) y = x -1

Rearrange equation 2 so that x and y are on the same side. To do so, you subtract x from both sides.

2) -x + y = -1
1) 2x - 3y = -1

Multiply ALL of equation 2 by 2.

2) 2(-x + y = -1)

Simplify.

2) -2x + 2y = -1
1) 2x - 3y = -1

Add equations together.

-y = 0

So, y = 0

Plug in 0 for y in the first equation.

2x - 3y = -1

2x - 3(0) = -1

Simplify.

2x - 0 = -1

2x = -1

Divide both sides by 2.

x = -1/2

(-1/2 , 0)

~Hope I helped!~
User Skander
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