SOLUTION: How do I solve the system of equations using the Gauss-Jordan elimination? 3x+5y=7 6x-y=-8

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Question 175531: How do I solve the system of equations using the Gauss-Jordan elimination?
3x+5y=7
6x-y=-8
Found 2 solutions by stanbon, Mathtut:
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
solve the system of equations using the Gauss-Jordan elimination?
3x+5y=7
6x-y=-8
-------------
Multiply thru the 2nd equation by 5 to get:
30x - 5y = -40
Add that to the 1st equation to solve for "x":
33x = -33
x = -1
-------------
Substitute into 3x+5y=7 to solve for "y":
3*-1 + 5y = 7
5y = 10
y = 2
==================
Cheers,
Stan H.

Answer by Mathtut(3670) About Me  (Show Source):
You can put this solution on YOUR website!

start with augmented matrix
:
%28matrix%282%2C3%2C3%2C5%2C7%2C6%2C-1%2C-8%29%29(R1)/3%28matrix%282%2C3%2C1%2C5%2F3%2C7%2F3%2C6%2C-1%2C-8%29%29-6R1+R2%28matrix%282%2C3%2C1%2C5%2F3%2C7%2F3%2C0%2C-11%2C-22%29%29R2/-11%28matrix%282%2C3%2C1%2C5%2F3%2C7%2F3%2C0%2C1%2C2%29%29-(5/3)R2+R1highlight%28%28matrix%282%2C3%2C1%2C0%2C-1%2C0%2C1%2C2%29%29%29
:
answer is system%28x=-1%2Cy=2%29


remember that R1 is Row 1
.................R2 is Row 2
:
and when you see something like R1/3 that is all the elements in Row 1 being divided by 3. Maybe you'll see 6R1+R2..thats elements in Row 1 multiplied by 6 and added to elements in Row 2.