SOLUTION: Solve by Substitution {𝑦=3𝑥+2;2𝑥+𝑦=−8

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Question 1176765: Solve by Substitution {𝑦=3𝑥+2;2𝑥+𝑦=−8
Found 2 solutions by josgarithmetic, ikleyn:
Answer by josgarithmetic(39795) About Me  (Show Source):
You can put this solution on YOUR website!
The very obvious first step is 2x%2B%283x%2B2%29=-8.

Answer by ikleyn(53751) About Me  (Show Source):
You can put this solution on YOUR website!
.

You just have "y" expressed via "x" in the first equation.


So, substitute this expression of "y" into the second equation, re[placing "y" there.


You will get


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


      5x          = -8 - 2

      5x          = - 10

       x          = -10/5 = -2.


ANSWER.  x= -2;  y = 3x + 2 = 3*(-2) + 2 = -6 + 2 = -4.

Solved.