Алгебра: Решите систему уравнений x^2=7y+2 x^2+2=7y+y^2

Решите систему уравнений x^2=7y+2 x^2+2=7y+y^2

Ответы

DianaSims 03.10.2020 14:51

(-4; 2), (4;2).

Объяснение:

$\left \{ \begin{array}{lcl} {{x^{2}=7y+2,} \\ {x^{2} +2=7y+y^{2}; }} \end{array} \right.\Leftrightarrow\left \{ \begin{array}{lcl} {{x^{2}=7y+2,} \\ {7y+2+2=7y+y^{2} ;}} \end{array} \right.\Leftrightarrow\left \{ \begin{array}{lcl} {{x^{2}=7 y+2,} \\ {y^{2} =4;}} \end{array} \right.\Leftrightarrow\\\\\left \{ \begin{array}{lcl} {x^{2} =7y+2,} \\ {\left [ \begin{array}{lcl} {{y=2,} \\ {y=-2;}} \end{array} \right.}} \end{array} \right.$

$\Leftrightarrow\left [ \begin{array}{lcl} {{\left \{ \begin{array}{lcl} {{y=2,} \\ {x^{2} =7*2+2;}} \end{array} \right.} \\ {\left \{ \begin{array}{lcl} {{y=-2,} \\ {x^{2}=7*(-2)+2; }} \end{array} \right.}} \end{array} \right.\Leftrightarrow\left [ \begin{array}{lcl} {{\left \{ \begin{array}{lcl} {{y=2,} \\ {x^{2} =16;}} \end{array} \right.} \\ \left \{ \begin{array}{lcl} {{y=-2,} \\ {x^{2}=-12; }} \end{array} \right.{}} \end{array} \right.\Leftrightarrow$

$\left \{ \begin{array}{lcl} {{\left [ \begin{array}{lcl} {{x=-4,} \\ {x=4,}} \end{array} \right.} \\ {y=2;}} \end{array} \right.\Leftrightarrow \left [ \begin{array}{lcl} {{\left \{ \begin{array}{lcl} {{x=-4,} \\ {y=2;}} \end{array} \right.} \\ {\left \{ \begin{array}{lcl} {{x=4,} \\ {y=2.}} \end{array} \right.}} \end{array} \right.$