SOLUTION: solution of subtitution y=2x+7 y=x-1

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Question 863966: solution of subtitution
y=2x+7 y=x-1
Answer by mananth(16946) About Me  (Show Source):
You can put this solution on YOUR website!
-1 x + 1 y = -1 .............1
1 y = -1 + 1 x
/ 1 =
y = -1 + 1 x
-2 x + 1 y = 7 .....................2
Substitute y in (2)
-2 x + 1 ( -1 + 1 x ) = 7
-2 x + -1 + 1 x = 7
-2 x 1 x = 8
-1 x = 8
/ -1
x= -8
Plug the value of x in (1)
-1 x + 1 y = -1
-1 * -8 + 1 y = -1
8 + 1 y = -1
1 y = -9
/ 1
y= -9
m.ananth@hotmail.ca