0=12x^2-520x+4000

解答

0 = 12 x^{2} - 520 x + 4000

x = \frac{100}{3}, x = 10

十进制

x = 33.33333 \dots, x = 10

求解步骤

0 = 12 x^{2} - 520 x + 4000

交换两边

12 x^{2} - 520 x + 4000 = 0

使用求根公式求解

x_{1, 2} = \frac{- ( - 520 ) \pm ( - 520 ) ^{2} - 4 \cdot 12 \cdot 4000}{2 \cdot 12}

(- 520)^{2} - 4 \cdot 12 \cdot 4000 = 280

x_{1, 2} = \frac{- ( - 520 ) \pm 280}{2 \cdot 12}

将解分隔开

x_{1} = \frac{- ( - 520 ) + 280}{2 \cdot 12}, x_{2} = \frac{- ( - 520 ) - 280}{2 \cdot 12}

x = \frac{- ( - 520 ) + 280}{2 \cdot 12} : \frac{100}{3}

x = \frac{- ( - 520 ) - 280}{2 \cdot 12} : 10

二次方程组的解是:

x = \frac{100}{3}, x = 10

so l v e f or x, y = \frac{121}{5} - \frac{1}{5} x^{2}

4 (x^{2} - 30 x + 2500) = 0

6 y^{2} + y - 1 = (y + 5) (y - 1)

6 x^{2} - 9 x = 7

4 (\frac{2 y - 3}{2}) y - (\frac{2 y - 3}{2})^{2} - 3 (\frac{2 y - 3}{2}) = 0