Math help?
2016-11-21 4:01 pm
Write the correct factorization for 81x2 - 4 = 0. Then find the solution(s).
回答 (5)
2016-11-21 4:48 pm
( 9 x - 2 ) ( 9 x + 2 ) = 0
x = 2/9 , x = - 2/9
x = 2/9 , x = - 2/9
2016-11-21 4:41 pm
81x^2 - 4 = 0
(9x)^2 - (2)^2 = 0
(9x + 2)(9x - 2) = 0
Solutions:
x = -2/9
x = 2/9
(9x)^2 - (2)^2 = 0
(9x + 2)(9x - 2) = 0
Solutions:
x = -2/9
x = 2/9
2016-11-21 4:27 pm
81x^2 - 4 = 0
(9x)^2 -2^2 = 0
(9x+2)(9x-2) = 0
9x+2 = 0
9x=-2
x=-2/9 -----(1)
9x-2=0
9x=2
x=2/9 -----(2)
(1) & (2) are solutions
(9x)^2 -2^2 = 0
(9x+2)(9x-2) = 0
9x+2 = 0
9x=-2
x=-2/9 -----(1)
9x-2=0
9x=2
x=2/9 -----(2)
(1) & (2) are solutions
2016-11-21 4:06 pm
If the 2 is an exponent, it needs to written as ² or ^2.
81x² - 4 = 0
(9x+2)(9x-2) = 0
x = ±2/9
81x² - 4 = 0
(9x+2)(9x-2) = 0
x = ±2/9
2016-11-21 4:04 pm
The difference of squares is factored as
.. (9x -2)(9x +2) = 0
.. x = ±2/9
.. (9x -2)(9x +2) = 0
.. x = ±2/9
收錄日期: 2021-04-23 23:48:47
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https://hk.answers.yahoo.com/question/index?qid=20161121080117AAmrn3P