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Points of intersection

  1. Oct 14, 2014 #1
    1. The problem statement, all variables and given/known data

    Find the intersection points of y=3x^2 and y=3^x

    2. Relevant equations

    They must be found with graphing techniques and cannot be proved algebraically. The answers are (-.451,.0609), (1.3), and (3, 27).

    3. The attempt at a solution

    Table of values from -3 to 3 for x, and i can come up with (1,3) and (3, 27). I really don't know how to find an intersection like (-.451,.0609).

    not sure which graph to post here...

    for (3x^2)-(3^x)


    for y=3x^2 and y=3^x separately

    for (3x^2)-(3^x)


    for y=3x^2 and y=3^x separately

    Last edited: Oct 14, 2014
  2. jcsd
  3. Oct 14, 2014 #2


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    Gold Member
    2016 Award

    draw the graph of the lines and post your drawing, else we cannot help you.
  4. Oct 14, 2014 #3


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    Homework Helper

    On your graph of the difference, you can take the zeros. Use those for x and plug back into one of your equations to find y. Otherwise, plot the two functions on the same graph and do your best to estimate.
  5. Oct 14, 2014 #4
    ok thank you
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