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Thread: Solve for y

  1. #1
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    Solve for y

    y3 + 5 - y9=1/6
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  2. #2
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    Solve for y

    I Type it in wrong

    y/3 + 5 - y/9 = 1/6
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  3. #3
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    do you mean:

    $\displaystyle 3y+5 -9y = \frac{1}{6}$

    if so:

    $\displaystyle 3y+5 -9y = 5 - 6y = \frac{1}{6} $

    $\displaystyle 6y = 5-\frac{1}{6} = \frac{30}{6}-\frac{1}{6} = \frac{29}{6}$

    $\displaystyle y = \frac{29}{36}$



    OR do you mean:

    $\displaystyle y^3+5-y^9 = \frac{1}{6}$
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  4. #4
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    Quote Originally Posted by armygirltiff View Post
    y3 + 5 - y9=1/6
    Do you mean this?

    $\displaystyle 3y+5-9y=\frac{1}{6}$

    If so, then multiply the equation by six to get:

    $\displaystyle 18y+30-54y=1$

    Group the y's and constants on opposite sides

    $\displaystyle -36y=-29$

    Divide by -36 to get

    $\displaystyle y = \frac{29}{36}$
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  5. #5
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    no i mean
    y/3 + 5 -y/9=1/6
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  6. #6
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    Quote Originally Posted by armygirltiff View Post
    no i mean
    y/3 + 5 -y/9=1/6
    In the future put any corrections in the original thread. Do NOT just make a new one!!

    -Dan
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  7. #7
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    $\displaystyle \frac{y}{3}+5-\frac{y}{9} = \frac{1}{6}$

    $\displaystyle 3y+5-y = \frac{9}{6}$ (multiply both sides by 9)

    $\displaystyle 2y+5 = \frac{3}{2}$ (simplify)

    $\displaystyle 2y = \frac{3}{2}-5$ (subtract 5 from both sides)

    $\displaystyle 2y = \frac{-7}{2}$ (simplify)

    $\displaystyle y = \frac{-7}{4} $(divide both sides by 2)
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  8. #8
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    Quote Originally Posted by armygirltiff View Post
    no i mean
    y/3 + 5 -y/9=1/6
    $\displaystyle \frac{y}{3}+5-\frac{y}{9}=\frac{1}{6}$

    Multiply the equation by the lowest common denominator which happens to be 18!

    $\displaystyle 6y+90-2y=3$

    Combine y's on LS and constants on RS

    $\displaystyle 4y=-87$

    Divide by 4

    $\displaystyle y=\frac{-87}{4}$
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  9. #9
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    Quote Originally Posted by iknowone View Post
    $\displaystyle \frac{y}{3}+5-\frac{y}{9} = \frac{1}{6}$

    $\displaystyle 3y+5-y = \frac{9}{6}$ (multiply both sides by 9)

    $\displaystyle 2y+5 = \frac{3}{2}$ (simplify)

    $\displaystyle 2y = \frac{3}{2}-5$ (subtract 5 from both sides)

    $\displaystyle 2y = \frac{-7}{2}$ (simplify)

    $\displaystyle y = \frac{-7}{4} $(divide both sides by 2)
    Iknowone, you forgot to multiply 5 by 9!
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