2/x-1=9/2x-3?

2008-05-29 1:37 pm
Solve. Identify any extraneous solutions

回答 (11)

2008-05-29 1:45 pm
✔ 最佳答案
2/(x-1) = 9(2x-3)

multiply the denominators
=> 2(2x-3) = 9(x-1)
=> 4x -6 = 9x -9

=> -6 +9 = 9x - 4x
= 3 = 5x
=> x = 3/5
2008-05-29 1:49 pm
2/(x - 1) = 9/(2x - 3)
2(2x - 3) = 9(x - 1)
4x - 6 = 9x - 9
5x = 3
x = 3/5

Answer: x = 3/5

Proof:
2/(3/5 - 1) = 9/(2[3/5] - 3)
2/(3/5 - 5/5) = 9/(6/5 - 15/5)
2/(- 2/5) = 9/(- 9/5)
2(- 5/2) = 9(- 5/9)
- 10/2 = - 45/9
- 5 = - 5
2008-05-29 1:42 pm
2/(x-1) = 9/(2x-3)

4x-6/(x-1) = 9

4x-6= 9x-9
5x = 3
x= 3/5
2008-05-29 1:42 pm
simply cross multiply

2(2x-3)= 9( x-1)
4x-6= 9x-9
4x-9x= -9+6
-5x= -3
x= 3/5
2016-10-14 11:26 am
2e76a81a7ce35efbc634bb0add7223aa4(x - a million) = 9e76a81a7ce35efbc634bb0add7223aa4(2x - 3/5) 2(2x - 3/5) = 9(x - a million) 4x - 6 = 9x - 9 e76a81a7ce35efbc634bb0add7223aa4x = 3/5 x = e76a81a7ce35efbc634bb0add7223aa4e76a81a7ce35efbc634bb0add7223aa4e76a81a7ce35efbc634bb0add7223aa4 answer: x = e76a81a7ce35efbc634bb0add7223aa4e76a81a7ce35efbc634bb0add7223aa4e76a81a7ce35efbc634bb0add7223aa4 evidence: 2e76a81a7ce35efbc634bb0add7223aa4(e76a81a7ce35efbc634bb0add7223aa4e76a81a7ce35efbc634bb0add7223aa4e76a81a7ce35efbc634bb0add7223aa4 - a million) = 9e76a81a7ce35efbc634bb0add7223aa4(2[e76a81a7ce35efbc634bb0add7223aa4e76a81a7ce35efbc634bb0add7223aa4e76a81a7ce35efbc634bb0add7223aa4] - 3/5) 2e76a81a7ce35efbc634bb0add7223aa4(e76a81a7ce35efbc634bb0add7223aa4e76a81a7ce35efbc634bb0add7223aa4e76a81a7ce35efbc634bb0add7223aa4 - e76a81a7ce35efbc634bb0add7223aa4e76a81a7ce35efbc634bb0add7223aa4e76a81a7ce35efbc634bb0add7223aa4) = 9e76a81a7ce35efbc634bb0add7223aa4(6e76a81a7ce35efbc634bb0add7223aa4e76a81a7ce35efbc634bb0add7223aa4 - 1e76a81a7ce35efbc634bb0add7223aa4e76a81a7ce35efbc634bb0add7223aa4e76a81a7ce35efbc634bb0add7223aa4) 2e76a81a7ce35efbc634bb0add7223aa4(- 2e76a81a7ce35efbc634bb0add7223aa4e76a81a7ce35efbc634bb0add7223aa4) = 9e76a81a7ce35efbc634bb0add7223aa4(- 9e76a81a7ce35efbc634bb0add7223aa4e76a81a7ce35efbc634bb0add7223aa4) 2(- e76a81a7ce35efbc634bb0add7223aa4e76a81a7ce35efbc634bb0add7223aa42) = 9(- e76a81a7ce35efbc634bb0add7223aa4e76a81a7ce35efbc634bb0add7223aa49) - 10e76a81a7ce35efbc634bb0add7223aa42 = - 4e76a81a7ce35efbc634bb0add7223aa4e76a81a7ce35efbc634bb0add7223aa49 - 3/5 = - 3/5
2008-05-30 11:56 am
Question is incorrectly presented.
Should read as :-
2 / (x - 1) = 9 / (2x - 3)
2 (2x - 3) = 9 (x - 1)
4x - 6 = 9x - 9
3 = 5x
x = 3/5
2008-05-29 4:51 pm
x=3/5
2008-05-29 2:46 pm
2/(x - 1) = 9/(2x - 3)
2 = 9(x - 1)/(2x - 3)
2(2x - 3) = 9*x - 9*1
2*2x - 2*3 = 9x - 9
4x - 6 = 9x - 9
4x - 9x = 6 - 9
-5x = -3
x = -3/-5
x = 3/5 (0.6)
2008-05-29 1:50 pm
2/x-1 =9/2x-3

2/x +2 = 9/2x

2 = 9/2x - 2/x

2 = 9/2x - (2/2 * 2/x)

2 = 9/2x - 4/2x

2 = 5/2x

2 * 2/5 = x

4/5 = x

x = 0.8

Ahahahahaha
2008-05-29 1:45 pm
I fone reads this as (2/x) -1 = (9/2x) -3 the answer may be different. x = 5/4


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