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1. 方程$-(x - 4) = 9$的解为______.
答案
x=-5
解析
解：$-(x - 4) = 9$
$-x + 4 = 9$
$-x = 9 - 4$
$-x = 5$
$x = -5$
$-x + 4 = 9$
$-x = 9 - 4$
$-x = 5$
$x = -5$
2. 方程$2(x + 4) + 1 = -7$的解为______.
答案
x=-8
解析
解：$2(x + 4) + 1 = -7$
$2x + 8 + 1 = -7$
$2x + 9 = -7$
$2x = -16$
$x = -8$
$2x + 8 + 1 = -7$
$2x + 9 = -7$
$2x = -16$
$x = -8$
3. 方程$3(2x + 1) - 8x = -5$的解为______.
答案
x=4
解析
解：$3(2x + 1) - 8x = -5$
$6x + 3 - 8x = -5$
$-2x + 3 = -5$
$-2x = -8$
$x = 4$
$x=4$
$6x + 3 - 8x = -5$
$-2x + 3 = -5$
$-2x = -8$
$x = 4$
$x=4$
4. 方程$-6(\frac{1}{3}x + 5) + 2 = -4x$的解为______.
答案
x=14
解析
解：$-6(\frac{1}{3}x + 5) + 2 = -4x$
$-2x - 30 + 2 = -4x$
$-2x - 28 = -4x$
$-2x + 4x = 28$
$2x = 28$
$x = 14$
14
$-2x - 30 + 2 = -4x$
$-2x - 28 = -4x$
$-2x + 4x = 28$
$2x = 28$
$x = 14$
14
5. 方程$-4[2(t - 3)] + 3t = 26$的解为______.
答案
t=-$\frac{2}{5}$
解析
解：$-4[2(t - 3)] + 3t = 26$
$-8(t - 3) + 3t = 26$
$-8t + 24 + 3t = 26$
$-5t + 24 = 26$
$-5t = 2$
$t = -\frac{2}{5}$
$-8(t - 3) + 3t = 26$
$-8t + 24 + 3t = 26$
$-5t + 24 = 26$
$-5t = 2$
$t = -\frac{2}{5}$
6. 方程$0.4(2m - 1) - 5m = -2m$的解为______.
答案
m=-$\frac{2}{11}$
解析
解：$0.4(2m - 1) - 5m = -2m$
$0.8m - 0.4 - 5m = -2m$
$0.8m - 5m + 2m = 0.4$
$-2.2m = 0.4$
$m = -\frac{0.4}{2.2}$
$m = -\frac{2}{11}$
$m=-\frac{2}{11}$
$0.8m - 0.4 - 5m = -2m$
$0.8m - 5m + 2m = 0.4$
$-2.2m = 0.4$
$m = -\frac{0.4}{2.2}$
$m = -\frac{2}{11}$
$m=-\frac{2}{11}$
7. $4 - 3(x - 3) = x + 10$
答案
x=$\frac{3}{4}$
解析
解：$4 - 3(x - 3) = x + 10$
$4 - 3x + 9 = x + 10$
$-3x - x = 10 - 4 - 9$
$-4x = -3$
$x = \frac{3}{4}$
$4 - 3x + 9 = x + 10$
$-3x - x = 10 - 4 - 9$
$-4x = -3$
$x = \frac{3}{4}$
8. $7(a + 2) = 12 - 5(a + 2)$
答案
a=-1
解析
解：$7(a + 2) = 12 - 5(a + 2)$
$7a + 14 = 12 - 5a - 10$
$7a + 14 = 2 - 5a$
$7a + 5a = 2 - 14$
$12a = -12$
$a = -1$
$7a + 14 = 12 - 5a - 10$
$7a + 14 = 2 - 5a$
$7a + 5a = 2 - 14$
$12a = -12$
$a = -1$
9. $15 - (7 - 5x) = 2x + (5 - 3x)$
答案
x=-$\frac{1}{2}$
解析
解：15 - 7 + 5x = 2x + 5 - 3x
8 + 5x = -x + 5
5x + x = 5 - 8
6x = -3
x = -$\frac{1}{2}$
8 + 5x = -x + 5
5x + x = 5 - 8
6x = -3
x = -$\frac{1}{2}$
10. $3(x - 2) - 2[6 - 4(x + 3)] = 28$
答案
x=2
解析
$3(x - 2) - 2[6 - 4(x + 3)] = 28$
$3x - 6 - 2[6 - 4x - 12] = 28$
$3x - 6 - 2[-4x - 6] = 28$
$3x - 6 + 8x + 12 = 28$
$11x + 6 = 28$
$11x = 22$
$x = 2$
$3x - 6 - 2[6 - 4x - 12] = 28$
$3x - 6 - 2[-4x - 6] = 28$
$3x - 6 + 8x + 12 = 28$
$11x + 6 = 28$
$11x = 22$
$x = 2$
11. $3(x + 5) + 5[(x + 5) - 1] = 7(x + 5) - 1$
答案
x=-1
解析
解：$3(x + 5) + 5[(x + 5) - 1] = 7(x + 5) - 1$
$3(x + 5) + 5(x + 5) - 5 = 7(x + 5) - 1$
$8(x + 5) - 5 = 7(x + 5) - 1$
$8(x + 5) - 7(x + 5) = -1 + 5$
$x + 5 = 4$
$x = -1$
$3(x + 5) + 5(x + 5) - 5 = 7(x + 5) - 1$
$8(x + 5) - 5 = 7(x + 5) - 1$
$8(x + 5) - 7(x + 5) = -1 + 5$
$x + 5 = 4$
$x = -1$
12. $x - 6[2 - \frac{1}{2}(x - 4)] = 6x + 3$
答案
x=-$\frac{27}{2}$
解析
解：$x - 6\left[2 - \frac{1}{2}(x - 4)\right] = 6x + 3$
$x - 6\left[2 - \frac{1}{2}x + 2\right] = 6x + 3$
$x - 6\left[4 - \frac{1}{2}x\right] = 6x + 3$
$x - 24 + 3x = 6x + 3$
$4x - 24 = 6x + 3$
$4x - 6x = 3 + 24$
$-2x = 27$
$x = -\frac{27}{2}$
$x - 6\left[2 - \frac{1}{2}x + 2\right] = 6x + 3$
$x - 6\left[4 - \frac{1}{2}x\right] = 6x + 3$
$x - 24 + 3x = 6x + 3$
$4x - 24 = 6x + 3$
$4x - 6x = 3 + 24$
$-2x = 27$
$x = -\frac{27}{2}$
13. $2[\frac{2}{3}(1 - x) - 2] = 1$
答案
x=-$\frac{11}{4}$
解析
解：$2\left[\frac{2}{3}(1 - x) - 2\right] = 1$
$\frac{2}{3}(1 - x) - 2 = \frac{1}{2}$
$\frac{2}{3}(1 - x) = \frac{1}{2} + 2$
$\frac{2}{3}(1 - x) = \frac{5}{2}$
$1 - x = \frac{5}{2} × \frac{3}{2}$
$1 - x = \frac{15}{4}$
$-x = \frac{15}{4} - 1$
$-x = \frac{11}{4}$
$x = -\frac{11}{4}$
$\frac{2}{3}(1 - x) - 2 = \frac{1}{2}$
$\frac{2}{3}(1 - x) = \frac{1}{2} + 2$
$\frac{2}{3}(1 - x) = \frac{5}{2}$
$1 - x = \frac{5}{2} × \frac{3}{2}$
$1 - x = \frac{15}{4}$
$-x = \frac{15}{4} - 1$
$-x = \frac{11}{4}$
$x = -\frac{11}{4}$
14. $\frac{3}{2}[\frac{2}{3}(\frac{x}{4} - 1) - 2] - x = 2$
答案
x=-8
解析
解：$\frac{3}{2}\left[\frac{2}{3}\left(\frac{x}{4} - 1\right) - 2\right] - x = 2$
$\frac{3}{2}\left[\frac{x}{6} - \frac{2}{3} - 2\right] - x = 2$
$\frac{3}{2}\left(\frac{x}{6} - \frac{8}{3}\right) - x = 2$
$\frac{x}{4} - 4 - x = 2$
$-\frac{3}{4}x = 6$
$x = -8$
$\frac{3}{2}\left[\frac{x}{6} - \frac{2}{3} - 2\right] - x = 2$
$\frac{3}{2}\left(\frac{x}{6} - \frac{8}{3}\right) - x = 2$
$\frac{x}{4} - 4 - x = 2$
$-\frac{3}{4}x = 6$
$x = -8$
