Question

Помогите решить, пожалуйста!!!
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Answer 1

Ответ:

$(3;3);$  $(-2;-2);$  $(5\frac{5}{21}; -2\frac{13}{21});$$(2;1);(3;1);(-2;-1);(-3;-1);(3\sqrt{2};\sqrt{2});(2\sqrt{2};\sqrt{2});(-2\sqrt{2};-\sqrt{2});(-3\sqrt{2};-\sqrt{2});$Пошаговое объяснение:

$1) \left \{ {{4x-2y=6} \atop {6x+4y=30}} \right.$

$\left \{ {{8x-4y=12} \atop {6x+4y=30}} \right.$

$\left \{ {{8x-4y+6x+4y=12+30} \atop {6x+4y=30}} \right.$

$\left \{ {{14x=42} \atop {6x+4y=30}} \right.$

$\left \{ {{x=3} \atop {6x+4y=30}} \right.$

$\left \{ {{x=3} \atop {18+4y=30}} \right.$

$\left \{ {{x=3} \atop {4y=12}} \right.$

$\left \{ {{x=3} \atop {y=3}} \right.$

$(3;3);$

$2) \left \{ {{5x+y=-12} \atop {2x-3y=2}} \right.$

$\left \{ {{15x+3y=-36} \atop {2x-3y=2}} \right.$

$\left \{ {{15x+3y+2x-3y=-36+2} \atop {2x-3y=2}} \right.$

$\left \{ {{17x=-34} \atop {2x-3y=2}} \right.$

$\left \{ {{x=-2} \atop {2x-3y=2}} \right.$

$\left \{ {{x=-2} \atop {-4-3y=2}} \right.$

$\left \{ {{x=-2} \atop {3y=-6}} \right.$

$\left \{ {{x=-2} \atop {y=-2}} \right.$

$(-2;-2);$

$3) \left \{ {{\frac{x+y}{5}+2x=11} \atop {-\frac{3y}{5}+\frac{y-x}{15}=\frac{x}{5}}} \right.$

$\left \{ {{\frac{x+y}{5}*5+2x*5=11*5} \atop {-\frac{3y}{5}*15+\frac{y-x}{15}*15=\frac{x}{5}*15}} \right.$

$\left \{ {{x+y+10x=55} \atop {-3y*3+y-x=x*3}} \right.$

$\left \{ {{11x+y=55} \atop {-9y+y-x-3x=0}} \right.$

$\left \{ {{11x+y=55} \atop {-8y-4x=0}} \right.$

$\left \{ {{88x+8y=440} \atop {-8y-4x=0}} \right.$

$\left \{ {{88x+8y+(-8y)-4x=440+0} \atop {-8y-4x=0}} \right.$

$\left \{ {{84x=440} \atop {-8y-4x=0}} \right.$

$\left \{ {{21x=110} \atop {-8y-4x=0}} \right.$

$\left \{ {{x=\frac{110}{21}} \atop {-8y-4*\frac{110}{21}=0}} \right.$

$\left \{ {{x=5\frac{5}{21}} \atop {-8y=\frac{440}{21}}} \right.$

$\left \{ {{x=5\frac{5}{21}} \atop {y=-\frac{55}{21}}} \right.$

$\left \{ {{x=5\frac{5}{21}} \atop {y=-2\frac{13}{21}}} \right.$

$(5\frac{5}{21}; -2\frac{13}{21});$