Thực hiện phép tính

----- Nội dung ảnh -----
16) $\sqrt{x - 5y} = 2\sqrt{5}$
$\sqrt{5x - 2y} = 7$

17) $\sqrt{2x + y} = \sqrt{2} + 2$
$2\sqrt{2x - y} = 2\sqrt{2} - 2$

18) $\frac{2\sqrt{3x - 2y}}{5} = \frac{5}{2}$
$\sqrt{3x + 2\sqrt{2}y} = 10$

19) $5x - y\sqrt{2} = 4\sqrt{2}$
$2\sqrt{2} + y = 5$

20) $2(2x - 3) - (y + 2) = 4$
$3(2x - 3) - 2(y + 2) = -5$

21) $\frac{3}{2x - y} - \frac{6}{x + y} = 1$
$\frac{1}{2x - y} + \frac{y}{x + y} = 0$

22)
$$\begin{array}{ccc} 2(x + 1) & 5(y - 1) & = 9 \\ x - y & x + y & \\ 3(x + 1) & 5(y - 1) & = 21 \\ x - y & .x + y & = 11 \\ \end{array}$$

23)
$$\begin{array}{ccc} 5x + y & = 27 \\ x + 1 & y - 3 & \\ 2x & 3y & = 4 \\ x + 1 & 2x - y + 1 & = 5 \\ \end{array}$$

24)
$$\begin{array}{ccc} 4 & 5 & \\ x + y - 1 & 2x - y + 3 & \frac{5}{3} \\ x + y + 1 & 2x - y + 3 & -7 \\ \end{array}$$