1. 计算.
(1)$\frac {1}{3}\sqrt {0.09}+\frac {1}{5}\sqrt {0.25}$；
(2)$\sqrt {(-\frac {1}{5})^{2}}-\sqrt {(-6)^{2}}+\sqrt {1-(\frac {4}{5})^{2}}$.

1. (1)0.2. (2)$-5\frac {1}{5}$.

2. 用代入法解下列方程组.
(1)$\left\{\begin{array}{l} y= 2x,\\ 3y+2x= 8;\end{array} \right.$
(2)$\left\{\begin{array}{l} 2x+5y= -6,\\ x-3y= 8;\end{array} \right.$
(3)$\left\{\begin{array}{l} 2x+y= 3,\\ 3x-5y= 11;\end{array} \right.$
(4)$\left\{\begin{array}{l} 5x+2y= 23,\\ 3x-y= 5;\end{array} \right.$
(5)$\left\{\begin{array}{l} \frac {x}{3}+\frac {y}{4}= 2,\\ 5x-y= 11;\end{array} \right.$
(6)$\left\{\begin{array}{l} x+y= 9,\\ 3(x+y)+2x= 33.\end{array} \right.$

2. (1)$\left\{\begin{array}{l} x=1,\\ y=2.\end{array}\right.$ (2)$\left\{\begin{array}{l} x=2,\\ y=-2.\end{array}\right.$ (3)$\left\{\begin{array}{l} x=2,\\ y=-1.\end{array}\right.$
(4)$\left\{\begin{array}{l} x=3,\\ y=4.\end{array}\right.$ (5)$\left\{\begin{array}{l} x=3,\\ y=4.\end{array}\right.$ (6)$\left\{\begin{array}{l} x=3,\\ y=6.\end{array}\right.$