SOLUTION: Can you help me solve the following using substitution method x+2y=8 4x-2y=12

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Question 1152004: Can you help me solve the following using substitution method
x+2y=8
4x-2y=12
Found 3 solutions by MathLover1, Alan3354, MathTherapy:
Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!
x%2B2y=8........eq.1
4x-2y=12........eq.2
-----------------------------
x%2B2y=8........eq.1..solve for x
x=8-2y........eq.1a...=> substitute in eq.2

4%288-2y%29-2y=12.......solve for y
32-8y-2y=12
32-10y=12
32-12=10y
20=10y
y=2.....=> substitute in eq.1a

x=8-2%2A2........eq.1a
x=8-4
x=4
solution:
x=4,y=2
=> intersection of these two lines is at (4,2)








Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
Can you help me solve the following using substitution method
============
Subbing is not the best method here.
If you have a choice, use elimination.
-------------

 x + 2y = 8
4x - 2y = 12
--------------------- Add
5x = 20
etc.
------

I understand that subbing might not be your idea.

Answer by MathTherapy(10552) About Me  (Show Source):
You can put this solution on YOUR website!

Can you help me solve the following using substitution method
x+2y=8
4x-2y=12
x + 2y = 8_____x = 8 - 2y ------ eq (i)

4x - 2y = 12 ----- eq (ii)

To use substitution, just solve ONE of the 2 equations for a variable that has 1 as its coefficient, as seen above

4(8 - 2y) - 2y = 12 ------ Substituting 8 - 2y for x in eq (ii)

32 - 8y - 2y = 12

- 10y = 20



Now, substitute 2 for y in eq (i) to find the value of x 

That's ALL!! Nothing COMPLEX!