Question

ДАЮ 15 БАЛОВ!

Вот скрин задания

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Answer 1

$\displaystyle\bf\\\left \{ {{5x+3y=7} \atop {-2x+4y=-8} \ |:2} \right. \\\\\\\left \{ {{5x+3y=7} \atop {-x+2y=-4} \ |\cdot 5} \right.\\\\\\+\left \{ {{5x+3y=7} \atop {-5x+10y=-20}} \right.\\ ------------\\13y=-13\\\\y=-13:13=-1\\\\x=2y+4=2\cdot(-1)+4=-2+4=2\\\\Otvet \ :(2 \ ; \ -1)$