m^2-20m-300=0

解

m^{2} - 20 m - 300 = 0

m = 30, m = - 10

解答ステップ

m^{2} - 20 m - 300 = 0

解くとthe二次式

m_{1, 2} = \frac{- ( - 20 ) \pm ( - 20 ) ^{2} - 4 \cdot 1 \cdot ( - 300 )}{2 \cdot 1}

(- 20)^{2} - 4 \cdot 1 \cdot (- 300) = 40

m_{1, 2} = \frac{- ( - 20 ) \pm 40}{2 \cdot 1}

解を分離する

m_{1} = \frac{- ( - 20 ) + 40}{2 \cdot 1}, m_{2} = \frac{- ( - 20 ) - 40}{2 \cdot 1}

m = \frac{- ( - 20 ) + 40}{2 \cdot 1} : 30

m = \frac{- ( - 20 ) - 40}{2 \cdot 1} : - 10

二次equationの解:

m = 30, m = - 10