x^2-8x+16=25

解答

x^{2} - 8 x + 16 = 25

x = 9, x = - 1

求解步骤

x^{2} - 8 x + 16 = 25

将

25

para o lado esquerdo

x^{2} - 8 x - 9 = 0

使用求根公式求解

x_{1, 2} = \frac{- ( - 8 ) \pm ( - 8 ) ^{2} - 4 \cdot 1 \cdot ( - 9 )}{2 \cdot 1}

(- 8)^{2} - 4 \cdot 1 \cdot (- 9) = 10

x_{1, 2} = \frac{- ( - 8 ) \pm 10}{2 \cdot 1}

将解分隔开

x_{1} = \frac{- ( - 8 ) + 10}{2 \cdot 1}, x_{2} = \frac{- ( - 8 ) - 10}{2 \cdot 1}

x = \frac{- ( - 8 ) + 10}{2 \cdot 1} : 9

x = \frac{- ( - 8 ) - 10}{2 \cdot 1} : - 1

二次方程组的解是:

x = 9, x = - 1

f a c t or x^{2} - 26 x + 25

s im pl i f y \frac{( 2 x ^{2} ) ^{3} y ^{2}}{4 x ^{4} y ^{2}}

f a c t or 4 p q^{2} + 5 q r + 3 pq r

3 (y + 1) + 2 y = 5 (y - 1) + 5

(46.8)^{2} + (21.6)^{2} = c^{2}