solve the equation 4x^2+7x-2=0?
回答 (8)
2008-08-24 6:21 am
✔ 最佳答案
4x² + 7x - 2 = 04 (x² + 7/4 - 2/4 ) = 0
4 (x² + 7/4 - 1/2 ) = 0
4 (x + 2) (x - 1/4) = 0
x = -2, x = 1/4
2008-08-24 1:16 pm
use the all powerful quadratic formula x=(-b+-sqrt(b^2-4ac))/(2a)
a=4, b=7, c=-2
x=(-7+-sqrt(81))/8
x=1/4 and -2
make it a good day
a=4, b=7, c=-2
x=(-7+-sqrt(81))/8
x=1/4 and -2
make it a good day
2008-08-25 3:11 am
(4x - 1)(x + 2) = 0
x = 1/4 , x = - 2
x = 1/4 , x = - 2
2008-08-24 7:32 pm
4x^2 + 7x - 2 = 0
4x^2 + 8x - x - 2 = 0
(4x^2 + 8x) - (x + 2) = 0
4x(x + 2) - 1(x + 2) = 0
(x + 2)(4x - 1) = 0
x + 2 = 0
x = -2
4x - 1 = 0
4x = 1
x = 1/4 (0.25)
â´ x = -2 , 1/4 (0.25)
4x^2 + 8x - x - 2 = 0
(4x^2 + 8x) - (x + 2) = 0
4x(x + 2) - 1(x + 2) = 0
(x + 2)(4x - 1) = 0
x + 2 = 0
x = -2
4x - 1 = 0
4x = 1
x = 1/4 (0.25)
â´ x = -2 , 1/4 (0.25)
2008-08-24 1:21 pm
I get:
(4x-1)(x+2) = 0
x = 1/4, -2
(4x-1)(x+2) = 0
x = 1/4, -2
2008-08-24 1:21 pm
It's hard to write here the formula so you check this site
http://www.purplemath.com/modules/quadform.htm
In this case a=4 b=7 c=2
http://www.purplemath.com/modules/quadform.htm
In this case a=4 b=7 c=2
2008-08-24 1:18 pm
(4x -1)(x +2) = 0
4x - 1 = 0 or x + 2 = 0
4x = 1 or x = -2
x = 1/4 or x = -2
Hope that helps.
4x - 1 = 0 or x + 2 = 0
4x = 1 or x = -2
x = 1/4 or x = -2
Hope that helps.
2008-08-24 1:16 pm
(x+2)(4x-1)=0 so x = -2 or 1/4
收錄日期: 2021-05-01 11:01:35
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20080823221211AAPIJUx