Question

Актуально до 12 часов
Помогите кто знает

Answer 1

Ответ:

Пошаговое объяснение:

1)

$\displaystyle \left \{ {{3x-y=4\hfill} \atop {4x+3y=1 }} \right. \left \{ {{y=3x-4\hfill} \atop {4x+3(3x-4)=1}} \right. \left \{ {{y=3x-4\hfill} \atop {13x=13\hfill}} \right. \left \{ {{y=-1} \atop {x=1}} \right.$

2)

$\displaystyle \left \{ {{x-y=2\hfill} \atop {x^2-y^2=12}} \right. \left \{ {{x=2+y\hfill} \atop {4+4y+y^2-y^2=12} \right. \left \{ {{x=2+y} \atop {4y=8\hfill}} \right. \left \{ {{x=4} \atop {y=2}} \right.$

3)

$\displaystyle \left \{ {{x+y=4\hfill} \atop {x^2-xy+y^2=52}} \right. \left \{ {{x=4-y\hfill} \atop {16-8y+y^2-4y+y^2+y^2=52}} \right. \left \{ {{x=4-y\hfill} \atop {3y^2-12y-36=0}} \right.$

$\displaystyle \left \{ {{x_1=-2;\quad x_2=6} \atop {y_1= 6;\quad y_2 = -2}} \right.$

4)

$\displaystyle \left \{ {{2y-x=6\hfill} \atop {\displaystyle 9^{2x+y}=3^{2-3y}}}} \right. \left \{ {{x=2y-6\hfill} \atop {\displaystyle 3^{4x+2y}=3^{2-3y}}} \right. \left \{ {{x=2y-6\hfill} \atop {4x+2y=2-3y}} \right. \left \{ {{x=2y-6} \atop {4x+5y=2}} \right.$

$\displaystyle \left \{ {{x=2y-6\hfill} \atop {8y-24+5y=2}} \right. \left \{ {{x=2y-6} \atop {13y=26\hfill}} \right. \left \{ {{x=-2} \atop {y=2\hfill}} \right.$