-15= 3/7 b

解答

- 15 = \frac{3}{7} b

b = - 35

求解步骤

- 15 = \frac{3}{7} b

交换两边

\frac{3}{7} b = - 15

在两边乘以

7

3 b = - 105

两边除以

3

b = - 35

0 = 2 d - 16

∣ 4 - x ∣ = ∣ 2 x + 1 ∣

x^{2} + 21 x - 20 \geq 4 x - 80

4 x^{2} = 4 x

105 n^{3} + 175 n^{2} - 75 n - 125