Ask Experts Questions for FREE Help !
Ask
    j4gym's Avatar
    j4gym Posts: 1, Reputation: 1
    New Member
     
    #1

    Sep 20, 2009, 03:01 PM
    Pre calc equation
    How do you solve this problem?
    3^2x+ 3^x -12 = 0
    and can you do the steps for me to also please.
    Perito's Avatar
    Perito Posts: 3,139, Reputation: 150
    Ultra Member
     
    #2

    Sep 20, 2009, 08:11 PM
    How do you solve this problem?
    3^2x+ 3^x -12 = 0
    It's fairly simple as soon as you realize you can factor it.





    and can you do the steps for me to also please.
    I wish I could (actually, I don't -- but I'm lazy). Just create two equations from the above equation. Move the constant to the right in each equation and take the logarithm of both sides.
    Unknown008's Avatar
    Unknown008 Posts: 8,076, Reputation: 723
    Uber Member
     
    #3

    Sep 20, 2009, 11:22 PM

    Okay, the easiest way to do this is by a simple substitution.

    Let

    Then,






    Now, you can solve it like any other quadratic;



    Then,

    y = -4or
    y = 3

    Replace y by 3^x




    Since 3^x cannot be negative, it must be the other one.



    So, x = 1

    :)

Not your question? Ask your question View similar questions

 

Question Tools Search this Question
Search this Question:

Advanced Search

Add your answer here.


Check out some similar questions!

Word Equation for Pre Calc [ 1 Answers ]

The sun iluminates half of the moon's surface, except during a lunar eclipse. The illuminated portion of the moon visible from Earth varies as t revolves around Earth resulting in the phases of the moon. The period from a full moon to a new moon and back o a full moon is called a synodic month...

How to calc w/h & what else to pay in Atlanta? [ 10 Answers ]

Hello! I am an S-Corp (single owner). I was paid by my client since Oct. 2007 and I have registered with GA DOL, DOR etc. I think I have to pay w/h by Jan. 15, 2008. 1. I transferred money two times in the last 3 months into my personal account. Is this a salary or "draw"? Am I better off...

Pre-calc trig [ 2 Answers ]

State the amplitude and period of the sinusoid, and (relative to the basic function) the phase shift and vertical translation. y= 2/3 cos (/4) +1

Calc hw [ 2 Answers ]

how do I know if its derivative or just find the y in an equation?


View more questions Search