20a^2+132a+160=0

解

20 a^{2} + 132 a + 160 = 0

a = - \frac{8}{5}, a = - 5

十進法表記

a = - 1.6, a = - 5

解答ステップ

20 a^{2} + 132 a + 160 = 0

解くとthe二次式

a_{1, 2} = \frac{- 132 \pm 13 2 ^{2} - 4 \cdot 20 \cdot 160}{2 \cdot 20}

13 2^{2} - 4 \cdot 20 \cdot 160 = 68

a_{1, 2} = \frac{- 132 \pm 68}{2 \cdot 20}

解を分離する

a_{1} = \frac{- 132 + 68}{2 \cdot 20}, a_{2} = \frac{- 132 - 68}{2 \cdot 20}

a = \frac{- 132 + 68}{2 \cdot 20} : - \frac{8}{5}

a = \frac{- 132 - 68}{2 \cdot 20} : - 5

二次equationの解:

a = - \frac{8}{5}, a = - 5