SOLUTION: How do I use cramer's rule to solve the system of equation: -3x-4y=9 9x+10y=-3

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Question 907873: How do I use cramer's rule to solve the system of equation:
-3x-4y=9
9x+10y=-3
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
How do I use cramer's rule to solve the system of equation:
-3x-4y=9
9x+10y=-3
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The coefficient matrix determinant = (-3*10)-(-4*9) = 6
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The X-matrix determinant = (9*10)-(-3*-4) = 78
The Y-matrix determinant = (-3*-3)- (9*9) = 9-81 = -72
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x = 78/6 = 13
y = -72/6 = -12

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Cheers,
Stan H.