1. 解方程:
(1) $7x - 21 = 1$;
(2) $5x - 3 = 2x$;
(3) $2x = 3x - 5$;
(4) $8 - 5y = y + 2$;
(5) $5 + 3x = 8 + 2x$;
(6) $6x - 7 = 4x - 5$;
(7) $2x - 3 = 3x + 4$;
(8) $4 - 3x = 6 - 5x$.

(1)$x=\frac{22}{7}$
(2)$x=1$
(3)$x=5$
(4)$y=1$
(5)$x=3$
(6)$x=1$
(7)$x=-7$
(8)$x=1$

2. 解方程：
(1)$0.1x+5=x-4$；
(2)$x-3=-\dfrac{1}{3}x+1$。

(1)$x=10$
(2)$x=3$