zs

English

Español

Português

Français

Deutsch

Italiano

Русский

中文(简体)

한국어

日本語

Tiếng Việt

עברית

العربية

受欢迎的代数 >

3x^2+18x+2lx=0,12y+2ly=0,x^2+y^2=9

解答

3 x^{2} + 18 x + 2 l x = 0, 12 y + 2 l y = 0, x^{2} + y^{2} = 9

解答

(x = 3, y = 0, l = - \frac{27}{2})

求解步骤

3 x^{2} + 18 x + 2 l x = 0 12 y + 2 l y = 0 x^{2} + y^{2} = 9

对于

3 x^{2} + 18 x + 2 l x = 0

将

l

移到一边:

l = - \frac{3 ( x + 6 )}{2}; x \neq = 0

将

l = - \frac{3 ( x + 6 )}{2}

代入

12 y + 2 l y = 0

12 y + 2 (- \frac{3 ( x + 6 )}{2}) y = 0

化简

- 3 x y - 6 y = 0

解方程组:

- 3 x y - 6 y = 0, x^{2} + y^{2} = 9 : x = 3, x = - 3, x = - 2, x = - 2, y = 0 y = 0 y = 5 y = - 5

将解代入原方程进行验证

因而，

3 x^{2} + 18 x + 2 l x = 0, 12 y + 2 l y = 0, x^{2} + y^{2} = 9

最后的解是

(x = 3, y = 0, l = - \frac{27}{2})

流行的例子

c^{2} = 1^{2} + x^{2}

10 x^{2} + 37 x + 7 = 0

- 4 = x^{2} - x - 6

a^{2} - 6 a - 27 = 0

4y^2-2400y+1442000=0

4 y^{2} - 2400 y + 1442000 = 0