Question

Пж допоможіть.Даю 40 бл.Очень прошу вас

Answer 1

Ответ:

$1)\ \ \left\{\begin{array}{l}5(x-2)+7=9+4x\\4(x-y)-5y=39\end{array}\right\ \ \left\{\begin{array}{l}5x-10+7=9+4x\\4x-4y-5y=39\end{array}\right\ \ \left\{\begin{array}{l}x=12\\4x-9y=39\end{array}\right\\\\\\\left\{\begin{array}{l}x=12\\9y=4x-39\end{array}\right\ \ \left\{\begin{array}{l}x=12\\9y=9\end{array}\right\ \ \left\{\begin{array}{l}x=12\\y=1\end{array}\right\ \ \ Otvet:\ \ (\, 12\, ;\, 1\, )\ .$

$2)\ \ \left\{\begin{array}{l}\dfrac{1}{3}\Big(x-y\Big)=4\\\ \dfrac{1}{4}\Big(x+y\Big)=2\end{array}\right\ \ \left\{\begin{array}{l}x-y=12\\x+y=8\end{array}\right\ \oplus \ominus \ \left\{\begin{array}{l}2x=20\\-2y=4\end{array}\right\ \ \left\{\begin{array}{l}x=10\\y=-2\end{array}\right\\\\\\Otvet:\ \ (\, 10\ ;-2\, )\ .$