Question

Помогите с 3 пожалуйста

Answer 1

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Answer 2

Ответ:

$(1; -3)$

Объяснение:

$3) \left \{ {{\frac{x}{3}-\frac{y-2x}{5}=1\frac{1}{3} \quad | \quad \cdot 15} \atop {\frac{y}{2}+\frac{5}{6}=\frac{x+y}{3} \quad | \quad \cdot 6}} \right. \Leftrightarrow \left \{ {{5x-3(y-2x)=20} \atop {3y+5=2(x+y)}} \right. \Leftrightarrow \left \{ {{5x-3y+6x=20} \atop {3y+5=2x+2y}} \right. \Leftrightarrow \left \{ {{11x-3y=20} \atop {y-2x=-5}} \right. \Leftrightarrow$

$\Leftrightarrow \left \{ {{11x-3(2x-5)=20} \atop {y=2x-5}} \right. \Leftrightarrow \left \{ {{11x-6x+15=20} \atop {y=2x-5}} \right. \Leftrightarrow \left \{ {{5x=5} \atop {y=2x-5}} \right. \Leftrightarrow \left \{ {{x=1} \atop {y=2 \cdot 1-5}} \right. \Leftrightarrow \left \{ {{x=1} \atop {y=-3}} \right. ;$

$(1; -3);$