Найдите точку пересечения прямых: 2x-3=y и 3x+y=7

2x - y = 3 3x + y = 7  ----------------- +  5x = 10 x = 2 y = 7 - 3x = 7 - 6 = 1 

[latex] \left \{ {{2x-3=y} \atop {3x+y=7}} \right. [/latex] [latex] \left \{ {{2x-y=3} \atop {3x+y=7}} \right. [/latex] [latex] \left \{ {{5x=10} \atop {y=7-3x}} \right. [/latex] [latex] \left \{ {{x=2} \atop {y=7-3*2}} \right. [/latex] [latex] \left \{ {{x=2} \atop {y=1}} \right. [/latex] Ответ: (2;1) или  [latex]2x-3=y [/latex]   ⇒ [latex]y=2x-3[/latex] [latex]3x+y=7[/latex]   ⇒ [latex]y=7-3x[/latex] [latex]2x-3=7-3x[/latex] [latex]2x+3x=7+3[/latex] [latex]5x=10[/latex] [latex]x=2[/latex] [latex]y=2*2-3=1[/latex] Ответ: (2;1)