Giải thích các bước giải:
Thế
\(\begin{array}{l}
a.\left\{ \begin{array}{l}
y = 3x - 5\\
5x + 6x - 10 = 23
\end{array} \right. \to \left\{ \begin{array}{l}
x = 3\\
y = 4
\end{array} \right.\\
b.\left\{ \begin{array}{l}
x = \frac{{11 + 3y}}{2}\\
- 22 - 6y + 6y = 5
\end{array} \right. \to \left\{ \begin{array}{l}
0y = 27\left( {voli} \right)\\
x = \frac{{11 + 3y}}{2}
\end{array} \right.
\end{array}\)
⇒ Pt vô nghiệm
\(c.\left\{ \begin{array}{l}
x = \frac{{10 + 2y}}{3}\\
10 + 2y - 2y = 10
\end{array} \right. \to \left\{ \begin{array}{l}
x = \frac{{10 + 2y}}{3}\\
0y = 0\left( {ld} \right)
\end{array} \right.\)
⇒Pt vô số nghiệm
\(d.\left\{ \begin{array}{l}
y = 2 - 4x\\
7x - 6 + 12x = 5
\end{array} \right. \to \left\{ \begin{array}{l}
x = \frac{{11}}{{19}}\\
y = - \frac{6}{{19}}
\end{array} \right.\)
