SOLUTION: use the gauss-jordon method to solve the following systems of equations. x+y=7

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Question 802752: use the gauss-jordon method to solve the following systems of equations. x+y=7
x-y=4
thank you so much for your time..
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!
x%2By=7
x-y=4
______________
write out the coefficients and the constant as follows:
x y |c
1 1| 7
1 -1 |4......add rows 2 and 1
_________
2 +0+ |11
1 -1| +4.....multiply by 2
______
2 +0+|+11
2 -2| 8...subtract 2 from 1
________
2 +0+| 11........divide by 2
+0+ 2 |+3........divide by 2
__________
1 +0+|+11%2F2........=> x=11%2F2 or x=5.5
+0+ 1| 3%2F2........=> y=3%2F2 or y=1.5
+graph%28+600%2C+600%2C+-10%2C+10%2C+-10%2C+10%2C+-x%2B7%2C+x-4%29+