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Math Help - Solving system

  1. #1
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    Solving system



    I tried to simplify it down and go to this point:



    I don't know if I did it right. From there, I have no idea what to do T_T The problem asks for a exact answer so everything must stay in radicals. I also don't know how to solve it using matrices...
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  2. #2
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    from the first equation ...

    \sqrt{3x} = 2y-1

    3x = (2y-1)^2

    x = \frac{(2y-1)^2}{3}

    sub for x in the second equation ...

    \frac{2(2y-1)^2}{3} + 5y^2 = 12

    2(2y-1)^2 + 15y^2 = 36

    expand, collect like terms, and solve the quadratic for y ... then go back and evaluate for x. note that x > 0.
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  3. #3
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    I solved for y and got

    I plugged it into the x equation to solve for x and it looks like this:



    Im not sure how to break that down =O Do I multiply the 2 by both the 4 and root 3192? What about the plus and minus?
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  4. #4
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    why bother? leave those ugly solutions as they are.

    use your calculator to check the two sets of solutions (x,y) in the original system.
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  5. #5
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    Im pretty sure my y is correct. However when I plugged x and y into one of the equations in my calculator, it didnt work O.o I plugged it in using parentheses in the right places too.

    Thanks for the help!
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