-2x^2+140x=0

解答

- 2 x^{2} + 140 x = 0

x = 0, x = 70

求解步骤

- 2 x^{2} + 140 x = 0

使用求根公式求解

x_{1, 2} = \frac{- 140 \pm 14 0 ^{2} - 4 ( - 2 ) \cdot 0}{2 ( - 2 )}

14 0^{2} - 4 (- 2) \cdot 0 = 140

x_{1, 2} = \frac{- 140 \pm 140}{2 ( - 2 )}

将解分隔开

x_{1} = \frac{- 140 + 140}{2 ( - 2 )}, x_{2} = \frac{- 140 - 140}{2 ( - 2 )}

x = \frac{- 140 + 140}{2 ( - 2 )} : 0

x = \frac{- 140 - 140}{2 ( - 2 )} : 70

二次方程组的解是:

x = 0, x = 70

7 x^{2} - 2 x - 2 = 0

(5 - x) (- 4 - x) + 18 = 0

co m pl e t es q u a re x^{2} - 12 + 26 = 0

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