Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Ok easy algebra kicking my kids butt and im new to this again!

  1. Apr 11, 2005 #1
    4(2-6y)+7=3(5-7y)
    ok this is problem i will try solve can you verify cuz i don't think 3y is an answer! please help me

    8-24y+7=15-21y
    15-24y=15-21y
    24y-21y
    3y ???

    hows this work????

    edited cuz the 1st responder pointed out a sign error i made thanks!
     
    Last edited: Apr 11, 2005
  2. jcsd
  3. Apr 11, 2005 #2
    You made a mistake in you calculation, 15-21y is not equal to 15+21y.
     
  4. Apr 11, 2005 #3
    your calculation is wrong. But, what are the instructions? i mean, are u trying to solve for y? And if ur solving for why, u need to clear it, leave y alone
     
    Last edited: Apr 11, 2005
  5. Apr 11, 2005 #4

    jtbell

    User Avatar

    Staff: Mentor

    Oops, you switched a sign on the right side...

    15 - 24y = 15 - 21y


    That line isn't complete: (also fixing the sign mistake above)

    0 = 24y - 21y
    0 = 3y

    Now, what's the only value of y that can make that true? :smile:
     
  6. Apr 11, 2005 #5
    directions say

    soulve the equation so i assume solve for y, most other of his problems are solving for some x or y value i.e. x=this or that
     
  7. Apr 11, 2005 #6
    Edit: This information has already been posted.

    He is probably trying to solve for the variable y. In his calculations above, he also forgot to complete the line "24y+21y" (which is incorrect) and show that it equals zero.
     
  8. Apr 11, 2005 #7

    dextercioby

    User Avatar
    Science Advisor
    Homework Helper

    Your algebra is fine and the only solution is y=0.Can u see why?

    Daniel.
     
  9. Apr 11, 2005 #8
    it would have to be 0

    i am going to say 0 and thanks for helping on old guy with kids homework, helps keep the brain on all cylinders :)
     
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook