1. $(-3) + 5 =$

2. $(-2) - (-7) =$

3. $(-4) \times 6 =$

4. $(-18) \div 3 =$

5. $(-5)^2 =$

6. $(-1)^{100} =$

7. $(-2)^3 =$

8. $|-8| =$

9. $(-3) \times (-4) =$

10. $0 \div (-5) =$

1. $(-15) + (+7) - (-8) - (+23)$

2. $(-3) \times (-9) - 8 \times (-5)$

3. $(-81) \div \frac{9}{4} \times \frac{4}{9} \div (-16)$

4. $(-1)^4 - \frac{1}{6} \times [2 - (-3)^2]$

5. $(-2)^3 + (-3) \times [(-4)^2 + 2] - (-3)^2 \div (-2)$

6. $-\frac{3}{4} \times (-8 + \frac{2}{3} - \frac{1}{3})$

7. $(-5) \times (-3\frac{6}{7}) + (-7) \times (-3\frac{6}{7}) + 12 \times (-3\frac{6}{7})$

8. $(-1)^{2023} + (-2)^3 \times \frac{1}{4} - |-3|$

1. 当 $a = -2$ 时，求 $3a + 2a - 5a$ 的值。

2. 当 $x = 3$ 时，求 $2x^2 - 3x + 1$ 的值。

3. 当 $m = -1$ 时，求 $m^3 - 2m^2 + 4$ 的值。

4. 当 $a = -2, b = 3$ 时，求 $a^2 - 2ab + b^2$ 的值。

5. 当 $x = -2, y = \frac{1}{2}$ 时，求 $3x^2y - 2xy^2 + xy$ 的值。

6. 当 $a = -1, b = 2$ 时，求 $2a^2b - 3ab^2 + a^2b - 2ab^2$ 的值。

1. $3a + 2b - 5a - b$

2. $2x^2 - 3x + 4x^2 + 5x$

3. $m^2n - 2mn^2 + 3mn^2 - 4m^2n$

4. $3(x+y) - 2(x+y) + 5(x+y)$

5. $a^2 - 2ab + b^2 - a^2 + 2ab - b^2$

6. $5xy - 2x^2y + 3xy - 4x^2y$

1. $(2a + 3b) - (a - 2b)$

2. $3(2x - y) - 2(3x + y)$

3. $a^2 - (2a^2 - 3a) + (a - a^2)$

4. $2(m^2 - n^2) - 3(m^2 + n^2)$

5. $4(x^2 - 2x + 1) - 3(2x^2 - x - 1)$

6. $5ab - [2ab - (3ab - 4ab)]$

1. $x + 5 = 12$

2. $3x - 7 = 20$

3. $2x + 3 = 5x - 6$

4. $4(x - 2) = 2(x + 3)$

5. $\frac{x}{2} - 3 = \frac{x}{3} + 1$

6. $\frac{2x - 1}{3} - \frac{3x - 4}{4} = 1$

1. $3a + 2b - 5a - b$

2. $2x^2 - 3x + 4x^2 + 5x$

3. $m^2n - 2mn^2 + 3mn^2 - 4m^2n$

4. $3(x+y) - 2(x+y) + 5(x+y)$

5. $a^2 - 2ab + b^2 - a^2 + 2ab - b^2$

6. $5xy - 2x^2y + 3xy - 4x^2y$

1. $(2a + 3b) - (a - 2b)$

2. $3(2x - y) - 2(3x + y)$

3. $a^2 - (2a^2 - 3a) + (a - a^2)$

4. $2(m^2 - n^2) - 3(m^2 + n^2)$

5. $4(x^2 - 2x + 1) - 3(2x^2 - x - 1)$

6. $5ab - [2ab - (3ab - 4ab)]$

1. $x + 5 = 12$

2. $3x - 7 = 20$

3. $2x + 3 = 5x - 6$

4. $4(x - 2) = 2(x + 3)$

5. $\frac{x}{2} - 3 = \frac{x}{3} + 1$

6. $\frac{2x - 1}{3} - \frac{3x - 4}{4} = 1$