SOLUTION: 0<(9x-27)^-1<1/9

Algebra.Com
Question 898933: 0<(9x-27)^-1<1/9
Found 2 solutions by CubeyThePenguin, ikleyn:
Answer by CubeyThePenguin(3113)   (Show Source): You can put this solution on YOUR website!
0 < 1/(9x-27) < 1/9
0 < 9x - 27 < 9
27 < 9x < 36

3 < x < 4

Answer by ikleyn(52794)   (Show Source): You can put this solution on YOUR website!
.

            The solution by  @CubeyThePenguin is  INCORRECT.

            I came to bring you a correct solution.


You start from this inequality


    0 < (9x-27)^(-1) < 1/9


It is equivalent to the system of two inequalities


    0 < (9x-27)^(-1)          (1)
and
        (9x-27)^(-1) < 1/9    (2)


connected with the service word "and".


First inequality (1)  is  0 < ;  it is equivalent to  9x - 27 > 0;  x - 3 > 0  and finally  x > 3.


        So for what is follows, we can assume x > 3.     (3)


Second inequality (2)  is   < 1/9;  it is equivalent to   < 1  and finally 

(taking into account that x > 3) it implies  1 < x-3; hence x > 4.   (4)


Thus we get the final answer  x > 4.


ANSWER.  The solution set is  x > 4.


                         Visual CHECK



       


      Figure.  Plot y =  (red)  and y =  (green)

Solved  (correctly).



RELATED QUESTIONS

|9x + 9| >... (answered by josgarithmetic)
Now I'm really stuck. Solving this quadratic equation by factoring so here's my problem: (answered by josh_jordan)
SOlve and explain: 9x-2 _____ 2-9x a) 1 b) 9x=2d c) -1 d) 0 e)... (answered by edjones)
(9x^9)^1/2 (answered by Fombitz)
27,-9,3,-1, (answered by josgarithmetic,ikleyn)
27,-9,3,-1, (answered by josgarithmetic)
9(x+1)=9x+1 (answered by littlebitlove,MathLover1)
9x-27/9x Simplify by removing factors of... (answered by jim_thompson5910)
Please help me solve by completing the squares: {{{(x^2) - (6x) = (27)}}} {{{(2x^2) (answered by stanbon)