9x^2+30x+25=0

解

9 x^{2} + 30 x + 25 = 0

x = - \frac{5}{3}

十進法表記

x = - 1.66666 \dots

解答ステップ

9 x^{2} + 30 x + 25 = 0

解くとthe二次式

x_{1, 2} = \frac{- 30 \pm 3 0 ^{2} - 4 \cdot 9 \cdot 25}{2 \cdot 9}

3 0^{2} - 4 \cdot 9 \cdot 25 = 0

x_{1, 2} = \frac{- 30 \pm 0}{2 \cdot 9}

x = \frac{- 30}{2 \cdot 9}

\frac{- 30}{2 \cdot 9} = - \frac{5}{3}

x = - \frac{5}{3}

二次equationの解:

x = - \frac{5}{3}