SOLUTION: 2x-5y=4 5x-7y=-1 solve by using the matrix row reduction method. I've been trying to work on this problem for hours but I'm stuck. Hopefully you can help me.

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Question 197720: 2x-5y=4
5x-7y=-1
solve by using the matrix row reduction method.
I've been trying to work on this problem for hours but I'm stuck. Hopefully you can help me.
Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website!
2x-5y=4
5x-7y=-1
solve by using the matrix row reduction method.
-------------------
2...-5...4
5...-7...-1
--------------------
Multiply thus the 1st row by 5 and the 2nd row by 2 to get:
10...-25...20
10...-14...-2
---------------------
Subtract the 1st row from the 2nd to get:
10...-25...20
0.....11...-22
--------------------------
Divide thru the 2nd row by 11 to get:
10...-25...20
0......1...-2
-----------------------------
Add 25 times the 2nd row to the 1st row to get:
10.....0...-30
0......1...-2
-------------------------
Divide thru the 1st row by 10 to get:
1.....0....-3
0.....1....-2
====================
Solution:
x = -3
y = -2
======================
Cheers,
Stan H.