SOLUTION: solve by substitution 2x + 4y = 8 -2x + y = 12

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Question 548133: solve by substitution
2x + 4y = 8
-2x + y = 12
Found 2 solutions by mananth, josmiceli:
Answer by mananth(16946) (Show Source):
You can put this solution on YOUR website!
2 x + 4 y = 8 .............1
1 y = 12 + 2 x ---------2
/ 1 =
y = 12 + 2 x
Substitute y in (1)
2 x + 4 ( 12 + 2 x ) = 8
2 x + 48 + 8 x = 8
2 x + 8 x = 8 -48
10 x = -40
/ 10
x= -4
Plug the value of x in (1)
2 x + 4 y = 8
2 * -4 + 4 y = 8
-8 + 4 y = 8
4 y = 16
/ 4
y= 4
m.ananth@hotmail.ca

Answer by josmiceli(19441) (Show Source):
You can put this solution on YOUR website!
(1)
(2)
---------------
Divide both sides of (1) by
(1)
(1)
----------------
Substitute (1) into (2)
(2)
(2)
(2)
(2)
--------------
And, since
(2)
(2)
(2)
(2)
--------------
The solution is ( -4, 4 )
check answer:
(2)
(2)
(2)
(20
OK
and
(1)
(1)
(1)
(1)
OK