SOLUTION: 2x-y=8 5x-2y=21 please solve using substitution method to solve the system of linear equations

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Question 724494: 2x-y=8 5x-2y=21 please solve using substitution method to solve the system of linear equations
Answer by mananth(16946) About Me  (Show Source):
You can put this solution on YOUR website!
2 x + -1 y = 8 .............1
-1 y = 8 + -2 x
/ -1 =
y = -8 + 2 x
5 x + -2 y = 21 .....................2
Substitute y in (2)
5 x + -2 ( -8 + 2 x ) = 21
5 x + 16 + -4 x = 21
5 x -4 x = 5
1 x = 5
/ 1
x= 5
Plug the value of x in (1)
2 x + -1 y = 8
2 * 5 + -1 y = 8
10 + -1 y = 8
-1 y = -2
/ -1
y= 2
m.ananth@hotmail.ca