$$\begin{cases}x + y = 5\\2 x - 3 y = 1\end{cases}$$

$$\begin{cases}\frac{2}{x} = 11\\x - 3 z^{2} = 0\\\frac{2 x}{7} + y - z = -3\end{cases}$$

$$\begin{cases}2 x = 2\\5 y = 10\\x + y + z = 3\end{cases}$$

$$\begin{cases}x = y^{3}\\x y = -5\end{cases}$$

$$\begin{cases}x + y = 3\\1 \frac{1}{y} + 1 \frac{1}{x} = \frac{2}{5}\end{cases}$$

$$\begin{cases}x + y - \sqrt{x y} = 5\\2 x y = 3\end{cases}$$

$$\begin{cases}x^{2} - 1 = \frac{y}{2} + 1\\1 - y^{2} = x + 2\end{cases}$$

$$\begin{cases}x + y = 5\pi\\\sin{x} + \cos{2y} = -1\end{cases}$$

$$\begin{cases}x_{1} + 2 x_{2} + 3 x_{3} - 2 x_{4} = 1\\2 x_{1} - x_{2} - 2 x_{3} - 3 x_{4} = 2\\3 x_{1} + 2 x_{2} - x_{3} + 2 x_{4} = -6\\2 x_{1} - 3 x_{2} + 2 x_{3} + x_{4} = 11\end{cases}$$

$$\begin{cases}x - y - 1 = 0\\x + y + 2 = 0\end{cases}$$

$$\begin{cases}2 x - 3 y = 5\\5 x + y = 4\end{cases}$$

$$\begin{cases}8 v + 2 x + 4 y + 6 z = 100\\9 v + 3 x + 5 y + 7 z = 116\\- 9 v + 3 x - 5 y + 7 z = -40\\8 v - 2 x + 4 y - 6 z = 36\end{cases}$$

$$\begin{cases}2 x - y = 3\\2 x + y = 9\end{cases}$$

$$\begin{cases}y - \frac{\log{\left(x \right)}}{\log{\left(3 \right)}} = 1\\x^{y} = 3^{12}\end{cases}$$