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2 years ago

− 10x− 6y= 12 4x+ 7y=− 14

Mathematics

1 answer:

Anestetic [448]2 years ago

5 0

Answer:

x = 0, y = -2

Step-by-step explanation:

$\left \{ {{-10x-6y=12} \atop {4x+7y=-14}} \right. = \left \{ {{-10x=12+6y} \atop {4x+7y=-14}} \right. = \left \{ {{x=\frac{12+6y}{-10} }(1) \atop {4x+7y=-14}} \right$

Replace x from formula (1) to formula (2), we got:

$4*\frac{12+6x}{-10}=-14 \frac{-2}{5}(12+6y)+7y=-14 \frac{-24}{5} + \frac{-12}{5}y+7y=-14 \frac{23}{5}y = \frac{-46}{5} y = -2\\=> x= \frac{12+6*(-2)}{-10} = 0$

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