вправа 1054 гдз 7 клас алгебра Мерзляк Полонський

7 клас ➠ алгебра ➠ Мерзляк Полонський


Вправа 1054

 

Відповідь: \begin{equation}1)\left\{\begin{matrix} \left ( 2x+1 \right )^{2}-\\ -\left ( 2x-y \right )\left ( 2x+y \right )=\\ =\left ( y+8 \right )\left ( y-10 \right ),\\ 4x\left ( x-5 \right )-\\ -\left ( 2x-3 \right )\left ( 2x-9 \right )=\\ =6y-104; \end{matrix}\right. \end{equation} \begin{equation}\left\{\begin{matrix} 4x^{2}+4x+1-\\ -4x^{2}+y^{2}=\\ =y^{2}-2y-80,\\ 4x^{2}-20x-4x^{2}+\\\ +24x-27=\\ =6y-104; \end{matrix}\right. \end{equation} \begin{equation}-\left\{\begin{matrix} 4x+2y=-81,\\4x-6y=-77; \end{matrix}\right. \end{equation} \begin{equation}\left\{\begin{matrix} 8y=-4,\\4x=-77+6y; \end{matrix}\right. \end{equation} \begin{equation}\left\{\begin{matrix} y=-0,5,\\x=-20; \end{matrix}\right. \end{equation} \begin{equation}2)\left\{\begin{matrix} \left ( x-2 \right )\left ( x^{2}+2x+4 \right )-\\ -x\left ( x-4 \right )\left ( x+4 \right )=\\ =20-20y,\\ \left ( 3x-2 \right ) \left ( 4y+5 \right )=\\ =2y\left ( 6x-1 \right )-58; \end{matrix}\right. \end{equation} \begin{equation}\left\{\begin{matrix} x^{3}-8-x^{3}+16x=\\ =20-20y,\\ 12xy+15x-8y-10=\\ =12xy-2y-58; \end{matrix}\right. \end{equation} \begin{equation}\left\{\begin{matrix} 16x+20y=28,\\15x-6y=-48; \end{matrix}\right. \end{equation} \begin{equation}\left\{\begin{matrix} 4x+5y=7,\\5x-2y=-16; \end{matrix}\right. \end{equation} \begin{equation}+\left\{\begin{matrix} 8x+10y=14,\\25x-10y=-80; \end{matrix}\right. \end{equation} \begin{equation}\left\{\begin{matrix} 33x=-66,\\2y=5x+16; \end{matrix}\right. \end{equation} \begin{equation}\left\{\begin{matrix} x=-2,\\y=3. \end{matrix}\right. \end{equation}