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Solve by substitution.s-2x + y = 8(3x + y = -2([?],[]

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You have the following system of equations:

-2x + y = 8

3x + y = -2

The previous system must be solved by substitution. Then, you proceed as follow:

You solve the first equation for y:

-2x + y = 8 add 2x both sides

y = 8 + 2x

You previous expression for y into the second equation, as follow:

3x + y = -2 replace y = 8 + 2x

3x + (8 + 2x) = -2 eliminate parenthesis

3x + 8 + 2x = -2 simplify similar terms left side

3x + 2x + 8 = -2

5x + 8 = -2 subtract 8 both sides

5x = -2 -8

5x = -10 divide by 5 both sides

x = -10/5

x = -2

Next, you replace the value of x into one of the given equation:

-2x + y = 8 replace x

-2(-2) + y = 8

4 + y = 8

y = 8 - 4

y = 4

Hence, the solution to the given system of equations is:

x = -2

y = 4

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