Answer :

konrad509
[tex]2x + 4y = 16\\ x - 7 = 4y\\\\ 2x + 4y = 16\\ x = 4y+7\\\\ 2(4y+7)+4y=16\\ 8y+14+4y=16\\ 12y=2\\ y=\frac{2}{12}=\frac{1}{6}\\\\ x=4\cdot\frac{1}{6}+7\\ x=\frac{4}{6}+7\\ x=\frac{2}{3}+\frac{21}{3}\\ x=\frac{23}{3}[/tex]
TehGuyy
Ugh why do you even have to use substitution method, the elimination method is so much easier in this instance... :/

Okay well first off you want to get x alone on one side of the equals sign.

x - 7 = -4y
  + 7    + 7
---------------
x = -4y + 7
Then you plugin -4y + 7 for x in the other equation.

2(-4y + 7) + 4y = 16
Then distribute.

-8y + 14 + 4y = 16
Combine like terms.

-4y + 14 = 16
       -14     -14
-----------------------
-4y = 2
----  ------
-4    -4

y = -0.5

x - 7 = -4(-0.5)
-----------------------
x - 7 = 2
   + 7  +7
----------------
x = 9

Then you plugin the answers for each variable to check, but I will let you do that.



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