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4 votes
X+4y= -12
-3x-14=y

Pls use substitution!

1 Answer

3 votes

Answer:

(-4,-2)

Explanation:

Since this is substitution, replace the y in the first equation with the one from the bottom.

x+4y=-12

-3x-14=y

x+4(-3x-14)=-12

Now you will solve the problem.

x+4(-3x-14)=-12

Distribute the 4

x-12x-56=-12

put the x's together

-11x-56=-12

add 56 to each side

-11x-56=-12

+56 +56

-11x=44

divide by -11

-11x=44

/-11 /-11

x=-4

Now, plug that x into one of the equations.I will do the top one because it is easy.

x+4y=-12

substitute x

(-4)+4y=-12

Now, solve the equation

-4+4y=-12

Add 4 to both sides

-4+4y=-12

+4 +4

4y=-8

Divide by 4 to both sides

4y=-8

/4 /4

y=-2

Your answer is a ordered pair, so use the format (x,y) to answer

(-4, -2)

User Daniel Bingham
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