Yahoo Answers is shutting down on May 4th, 2021 (Eastern Time) and beginning April 20th, 2021 (Eastern Time) the Yahoo Answers website will be in read-only mode. There will be no changes to other Yahoo properties or services, or your Yahoo account. You can find more information about the Yahoo Answers shutdown and how to download your data on this help page.

maths inequalities help please!?

x/(x+3) is greater than 1/(x-2)

any help is really appreciated, got my exam tomorrow

3 Answers

Relevance
  • 10 years ago
    Favorite Answer

    This is different from an equation. You cannot cross-multiply.

    Pull everything to one side and get a common denominator.

    X/(x+3)-1/(x-2) >0. The lcd is (x+3)(x-2)

    [X(x-2)-1(x+3)]/(x+3)(x-2)>0

    (x^2-2x-x-3)= x^2-3x-3 is the numerator, but does not factor

    So (x^2-3x-3)/(x+3)(x-2)>0

    you now have to find the zeroes of all the factors

    X= -3, or 2 are zeroes of the denominator. Unfortunately you have to use the quadratic formula for the numerator.

    X= (3+/-sqr(21))/2=3.9or-.8

    Now put all these numbers on a number line

    .......-3.......-.8........2..........3.9......

    So check all five regions to see which ones work!

    +...-3.....(-)......-8......(+).....2.....(-).....3.9....+.....

    so the solution is ( -infinity,-3) and( -.8,2) and (3.9, infinity)

    This is sooo much easier with a graphing calculator...just graph both sides and see where the first graph is above (>) the other.

    Good luck!

    Source(s): Math teacher
  • 10 years ago

    x/(x+3) > 1/(x-2)

    multiply both sides by (x + 3)(x - 2)

    now the inequality reads

    x^2 - 2x / (x + 3)(x - 2) > x + 3 / (x + 3)(x - 2)

    multiply both sides by (x + 3)(x - 2)

    now the inequality reads

    x^2 - 2x > x + 3

    x^2 - 3x - 3 > 0

    now use the quadratic formula.

  • ?
    Lv 4
    5 years ago

    There are two inequalities: 2w > eight AND 2w < 12 You can remedy it now. The first one says w > four. The moment one says w < 6. So the reply is "w > four AND w < 6". You can write this as "four < w < 6".

Still have questions? Get your answers by asking now.