SOLUTION: How to solve a linear equation using the substitution method? Just need an example, I have tried other ways, and have not been able to come up with the correct answer.

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Question 724136: How to solve a linear equation using the substitution method? Just need an example, I have tried other ways, and have not been able to come up with the correct answer.
Answer by mananth(16946) About Me  (Show Source):
You can put this solution on YOUR website!
1 x + 1 y = 300 .............1

150 x + 350 y = 75000 .............2
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1 x + 1 y = 300 .............1
1 y = 300 + -1 x
/ 1 =
y = 300 + -1 x
150 x + 350 y = 75000 .....................2
Substitute y in (2)
150 x + 350 ( 300 + -1 x ) = 75000
150 x + 105000 + -350 x = 75000
150 x -350 x = -30000
-200 x = -30000
/ -200
x= 150
Plug the value of x in (1)
1 x + 1 y = 300
1 * 150 + 1 y = 300
150 + 1 y = 300
1 y = 150
/ 1
y= 150
m.ananth@hotmail.ca