Question

Решите систему уравнений
{2x + 3y=1
{6x - 2y=14

Answer 1

Решение и ответ:

$\displaystyle\[\left\{\begin{array}{l}2x+3y=1\\6x-2y=14\end{array}\right.\Leftrightarrow\left\{\begin{array}{l}14\cdot(2x+3y)=14\\6x-2y=14\end{array}\right.\Leftrightarrow\left\{\begin{array}{l}28x+42y=14\\6x-2y=14\end{array}\right.\]$

28x + 42y = 6x - 2y

28x - 6x = -2y - 42y

22x = -44y

x = -44y ÷ 22 = -2y

2 · (-2y) + 3y = 1

-4y + 3y = 1

-y = 1   |·(-1)

y = -1

x = -2y = -2 · (-1) = 2

Ответ: x = 2; y= -1.