Odpowiedź :
Odpowiedź:
[tex]x + 2y = 19 \\ x = 19 - 2y[/tex]
[tex]2x - 3y = - 11 \\ 2(19 - 2y) - 3y = - 11 \\ - 7y = - 49 \\ y = 7[/tex]
[tex]x + 2 \times 7 = 19 \\ x = 19 - 14 \\ x = 5[/tex]
Odpowiedź:
[tex]\begin{cases}x+2y=19\\2x-3y=-11\end{cases}\\\\\\\begin{cases}x=19-2y\\2x-3y=-11\end{cases}\\\\\\2(19-2y)-3y=-11\\\\38-4y-3y=-11\\\\-7y=-11-38\\\\-7y=-49\ \ /:(-7)\\\\y=7\\\\\\x=19-2\cdot7=19-14=5\\\\\begin{cases}x=5\\y=7\end{cases}[/tex]