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2 years ago

Solve the system using elimination.

1 answer:

7 0

$\left \{ {{7x+5y=15\ \ |*4} \atop {-6x-4y=-14\ \ |*5}} \right. \\\\ \left \{ {{28x+20y=60} \atop {-30x-20y=-70}} \right. \\+------\\
-2x=-10\ \ \ |Divide\ by\ -2\\
x=5\\\\
5y=15-7x\\
5y=15-7*5\\
5y=15-35\\
5y=-20\ \ \ |:5\\
y=-4\\\\\ Solution\ is\ B(5,-4).$

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2 years ago

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