[tex]\left \{ {{7x+10y=3} \atop {2x+7=5y}} \right.[/tex]

[tex]\left \{ {{7x+10y=3} \atop {2x-5y=-7|*2}} \right.[/tex]

[tex]\left \{ {{7x+10y=3} \atop {4x-10y=-14}} \right.[/tex]

11х= -11

х= -11:11

х= -1

[tex]\left \{ {{x= -1} \atop {7*(-1)+10y=3}} \right.[/tex]

7*(-1)+10y=3

-7+10у=3

10у=3+7

10у=10

у=10:10

у=1

[tex]\left \{ {{x=-1} \atop {y=1}} \right.[/tex]

Ответ: ( -1  ; 1)

Ответ:

(-1;1)

Объяснение:

[tex]7x + 10y = 3 \\ y = \frac{2x + 7}{5} \\ \\ 7x + \frac{10(2x + 7)}{5} = 3 \\ \\ 7x + 2(2x + 7) = 3 \\ 7x + 4x + 14 = 3 \\ 11x = - 11 \\ x = - 1 \\ \\ y = \frac{2 \times ( - 1) + 7}{5} = 1 \\ \\ [/tex]

Ответ: (-1 ;1)