35x^2-70x-1680=0

解

35 x^{2} - 70 x - 1680 = 0

x = 8, x = - 6

解答ステップ

35 x^{2} - 70 x - 1680 = 0

解くとthe二次式

x_{1, 2} = \frac{- ( - 70 ) \pm ( - 70 ) ^{2} - 4 \cdot 35 ( - 1680 )}{2 \cdot 35}

(- 70)^{2} - 4 \cdot 35 (- 1680) = 490

x_{1, 2} = \frac{- ( - 70 ) \pm 490}{2 \cdot 35}

解を分離する

x_{1} = \frac{- ( - 70 ) + 490}{2 \cdot 35}, x_{2} = \frac{- ( - 70 ) - 490}{2 \cdot 35}

x = \frac{- ( - 70 ) + 490}{2 \cdot 35} : 8

x = \frac{- ( - 70 ) - 490}{2 \cdot 35} : - 6

二次equationの解:

x = 8, x = - 6