Ask Me Help Desk

Ask Me Help Desk (https://www.askmehelpdesk.com/forum.php)
-   Math & Sciences (https://www.askmehelpdesk.com/forumdisplay.php?f=402)
-   -   Math Quiz Questions (https://www.askmehelpdesk.com/showthread.php?t=32312)

  • Aug 22, 2006, 10:25 AM
    bosey
    Math Quiz Questions
    Help! I need to find the answer to the following two questions by 4:00 p.m. today. Any assistance you can provide will be greatly appreciated!

    Polynomial and Rational Inequalities:

    Problem: Solve : x^2 + 56 < 15x


    Equations Quadratic in Form:

    Problem: Solve: x^4 - 10x^2 +25 = 0
  • Aug 22, 2006, 06:41 PM
    dmatos
    Well, it's 9:30, so I'm guessing you missed your deadline or already figured this out. But, in case you still need some help (though I'm not going to do your homework for you), these questions are both about factoring.

    x^2 + 56 < 15x

    Step 1: rearrange so that all terms are on one side of the equation
    Step 2: factor to a form (x-a)(x-b)<0
    Step 3: solve (x-a)(x-b)=0
    Step 4: this should divide values of x up into three different domains - greater than b, less than a, and between a and b. Now figure out in which of these domains the original inequality holds true. It can be one, two, or all three of them.

    x^4 - 10x^2 + 25 = 0

    Step 1: let y = x^2, that means y^2=x^4. Make these substitutions
    Step 2: factor the quadratic equation, and solve for all possible answers for y
    Step 3: take your equations y=a and y=b, and substitute x^2 back in for y
    Step 4: solve for all possible values of x

    Cheers!

  • All times are GMT -7. The time now is 01:34 AM.