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Math Help - -3p+7=-3

  1. #1
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    -3p+7=-3

    -3p+7=-3
    -3p=-10
    -3p/3=-10/3
    -p=-10/3 or -p=-3 and 1/3

    but it doesn't seem to pass a check

    -3(-10/3)+7=17 not -3

    What am I doing wrong here?
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  2. #2
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    -p=-10/3 then p=10/3
    -3(10/3)+7=-10+7=-3
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  3. #3
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    2/3y+2=1/5+y

    Doh! Nevermind. I figured it out. A stupid mistake.


    2/3y+2=1/5+y
    15(2/3y+2)=15(1/5+y)
    10y+30=3+15y
    10y+30=15y+3
    30=5y+3
    27=5y
    27/5=y

    but when I check it

    2/3(27/5)+2=1/5+27/5
    2/3(27/5)+2=28/5
    54/15+2=28/5
    84/15=28/5

    I know I'm making a stupid mistake somewhere but what is it?
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  4. #4
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    Quote Originally Posted by djarcadian View Post
    Doh! Nevermind. I figured it out. A stupid mistake.


    2/3y+2=1/5+y
    15(2/3y+2)=15(1/5+y)
    10y+30=3+15y
    10y+30=15y+3
    30=5y+3
    27=5y
    27/5=y

    but when I check it

    2/3(27/5)+2=1/5+27/5
    2/3(27/5)+2=28/5
    54/15+2=28/5
    84/15=28/5

    I know I'm making a stupid mistake somewhere but what is it?
    your answer y=\frac{27}{5} is actually correct.

    \frac{2}{3}y + 2 = \frac{1}{5} + y

    \frac{2}{3}*\frac{27}{5} + 2 = \frac{1}{5} + \frac{27}{5}

    \frac{18}{5} + 2 = \frac{28}{5}

    \frac{28}{5}=\frac{28}{5}

    \frac{84}{15}=\frac{28}{5}

    its just the lowest term
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