SOLUTION: Solve the system of linear equations using the Gauss-Jordan elimination method x-2y=8; 3x+4y=4

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Question 685476: Solve the system of linear equations using the Gauss-Jordan elimination method
x-2y=8; 3x+4y=4
Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!

x-2y=8
+3x%2B4y=4
__________________
Add %28-3+%2A+row1%29 to row2
1 | -2 | 8|
0+| 10| -20|
Divide row2 by 10
1| -2| 8|
0+| 1| -2|

Add %282+%2A+row2%29 to row1
1| 0| 4|
0| 1| -2|
so, x=4 and y=-2
check it on a graph:
+graph%28+600%2C+600%2C+-10%2C+10%2C+-10%2C+10%2C+x%2F2-4%2C+-%283%2F4%29x%2B1%29+