Question 141192
Using the augmented matrices to solve the following 2X2 systems of equations. Final answer must be given in matrix form. 
Problem to solve: -5x + 7y =9
x + 10y = 21 
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1...10...21
-5...7....9
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Multiply 1st row by 5 and add to 2nd row to get:
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1...10...21
0...57..114
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Divide thru 2nd by 57 to get
1...10...21
0....1....2
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Multiply 2nd row by 10 and subtract from 1st row to get:
1....0....1
0....1....2
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Solution:
x = 1 ; y = 2
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Cheers
Stan H.