1. 去括号解方程的步骤是先根据去括号法则和乘法分配律去掉
括号
,再移项
、合并同类项
、化系数为1
,从而求解.答案：括号 移项 合并同类项 1
解析：
去括号解方程的步骤是先根据去括号法则和乘法分配律去掉括号，再移项、合并同类项、化系数为1，从而求解.
2. 如果有多重括号,一般先去小括号,再去中括号,最后去
随堂小练
大括号
；特别注意不能漏乘括号里面的项.随堂小练
答案：大括号
1. 方程$-(x - 1) = 1$的解是 (
A.$x = 2$
B.$x = 1$
C.$x = 0$
D.$x = - 1$
C
)A.$x = 2$
B.$x = 1$
C.$x = 0$
D.$x = - 1$
答案：C
解析：
解：去括号，得$-x + 1 = 1$
移项，得$-x = 1 - 1$
合并同类项，得$-x = 0$
系数化为1，得$x = 0$
答案：C
移项，得$-x = 1 - 1$
合并同类项，得$-x = 0$
系数化为1，得$x = 0$
答案：C
2. 在解方程$3(x + 2)-4(1 - x)= 2(x - 1)$时,下列去括号正确的是 (
A.$3x + 2-4 + x = 2x - 1$
B.$3x + 2-2 + x = 2x - 2$
C.$3x + 6-4-4x = 2x - 2$
D.$3x + 6-4 + 4x = 2x - 2$
D
)A.$3x + 2-4 + x = 2x - 1$
B.$3x + 2-2 + x = 2x - 2$
C.$3x + 6-4-4x = 2x - 2$
D.$3x + 6-4 + 4x = 2x - 2$
答案：D
解析：
解：对原方程$3(x + 2)-4(1 - x)= 2(x - 1)$去括号：
$3x + 6 - 4 + 4x = 2x - 2$
结论：D
$3x + 6 - 4 + 4x = 2x - 2$
结论：D
3. 将多项式$2(x + 2)-3(-4x + 2)$去括号得
$2x + 4 + 12x - 6$
,合并同类项得$14x - 2$
.答案：$2x + 4 + 12x - 6$ $14x - 2$
4. 方程$2(x - 2)-3(4x - 1)= 9(1 - x)$去括号得
$2x - 4 - 12x + 3 = 9 - 9x$
,这种变形的根据是去括号法则
.答案：$2x - 4 - 12x + 3 = 9 - 9x$ 去括号法则
5. 解方程：
(1)$8y - 3(3y + 2)= 6$； (2)$4(x + 3)= 7(x - 3)-6$；
(3)$4x + 3(2x - 3)= 11-2(x + 4)$； (4)$6(\frac{1}{2}x - 4)+2x = 5-(x - 1)$；
(5)$6x - 2(x + 1)= 2-(7 - x)$； (6)$4-(x + 3)= 2(x - 1)$.
(1)$8y - 3(3y + 2)= 6$； (2)$4(x + 3)= 7(x - 3)-6$；
(3)$4x + 3(2x - 3)= 11-2(x + 4)$； (4)$6(\frac{1}{2}x - 4)+2x = 5-(x - 1)$；
(5)$6x - 2(x + 1)= 2-(7 - x)$； (6)$4-(x + 3)= 2(x - 1)$.
答案：(1)$y = -12$ (2)$x = 13$ (3)$x = 1$ (4)$x = 5$ (5)$x = -1$ (6)$x = 1$
解析：
(1)解：$8y - 9y - 6 = 6$
$-y = 12$
$y = -12$
(2)解：$4x + 12 = 7x - 21 - 6$
$4x - 7x = -27 - 12$
$-3x = -39$
$x = 13$
(3)解：$4x + 6x - 9 = 11 - 2x - 8$
$10x - 9 = 3 - 2x$
$10x + 2x = 3 + 9$
$12x = 12$
$x = 1$
(4)解：$3x - 24 + 2x = 5 - x + 1$
$5x - 24 = 6 - x$
$5x + x = 6 + 24$
$6x = 30$
$x = 5$
(5)解：$6x - 2x - 2 = 2 - 7 + x$
$4x - 2 = x - 5$
$4x - x = -5 + 2$
$3x = -3$
$x = -1$
(6)解：$4 - x - 3 = 2x - 2$
$1 - x = 2x - 2$
$-x - 2x = -2 - 1$
$-3x = -3$
$x = 1$
$-y = 12$
$y = -12$
(2)解：$4x + 12 = 7x - 21 - 6$
$4x - 7x = -27 - 12$
$-3x = -39$
$x = 13$
(3)解：$4x + 6x - 9 = 11 - 2x - 8$
$10x - 9 = 3 - 2x$
$10x + 2x = 3 + 9$
$12x = 12$
$x = 1$
(4)解：$3x - 24 + 2x = 5 - x + 1$
$5x - 24 = 6 - x$
$5x + x = 6 + 24$
$6x = 30$
$x = 5$
(5)解：$6x - 2x - 2 = 2 - 7 + x$
$4x - 2 = x - 5$
$4x - x = -5 + 2$
$3x = -3$
$x = -1$
(6)解：$4 - x - 3 = 2x - 2$
$1 - x = 2x - 2$
$-x - 2x = -2 - 1$
$-3x = -3$
$x = 1$
6. 解方程：$3-[2(1 - 3x)-5]= 4(x - 1)+2$.
答案：$x = -4$
解析：
解：$3-[2(1 - 3x)-5]= 4(x - 1)+2$
$3-(2 - 6x - 5)=4x - 4 + 2$
$3-(-6x - 3)=4x - 2$
$3 + 6x + 3=4x - 2$
$6x + 6=4x - 2$
$6x - 4x=-2 - 6$
$2x=-8$
$x=-4$
$3-(2 - 6x - 5)=4x - 4 + 2$
$3-(-6x - 3)=4x - 2$
$3 + 6x + 3=4x - 2$
$6x + 6=4x - 2$
$6x - 4x=-2 - 6$
$2x=-8$
$x=-4$