SOLUTION: solve each equations by the substitution method 3x+y=-14 4x+3y=-22

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Question 999542: solve each equations by the substitution method
3x+y=-14
4x+3y=-22

Answer by ikleyn(52788) About Me  (Show Source):
You can put this solution on YOUR website!
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solve each equations by the substitution method
3x+y=-14
4x+3y=-22
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3x +  y = -14   (1)
4x + 3y = -22   (2)

Express y from the first equation, y = -3x - 14, and substitute it into the second equation. You will get single equation for the unknown x:

4x + 3*(-3x - 14) = -22.

Simplify and solve it:

4x - 9x - 42 = -22,

-5x = -22 + 42,

-5x = 20,

x = 20%2F%28-5%29 = -4.

Substitute it into the first equation (1). You will get the equation for y:

3%2A%28-4%29%29 + y = -14.

It implies y = -14 + 12 = -2.

Check yourself this solution.

Answer. x = -4, y = -2.