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

Help with a word problem

  1. Jun 28, 2011 #1
    The word problem: If the product of a number and -5 is reduced by 2, the result is 26 less than twice the opposite of the number. What is the number?

    I wrote it out like this:
    n x (-5) - 2 = 2(-n) - 26

    I'm really at a loss here. Normally when there's a variable, my teacher says to get the variable alone, but when there's two that share a number, I don't know what to do besides pick random numbers and see what happens :P

    Thanks in advance,
  2. jcsd
  3. Jun 28, 2011 #2


    User Avatar
    Science Advisor
    Homework Helper

    Hi Cyril! :smile:

    Just shove all the n's over to the LHS, and everything else to the RHS. :wink:
  4. Jun 28, 2011 #3
    Haha thanks :D

    So add 7 to the left to get rid of the -5 and - 2 (and add it to the right of course), but how do you move the variable from the right?
  5. Jun 28, 2011 #4


    User Avatar
    Science Advisor
    Homework Helper

    eugh! :yuck:

    perhaps i'd better start you off :wink:

    n x (-5) - 2 = 2(-n) - 26​

    let's rewrite that as

    -5n - 2 = -2n - 26 …​

    carry on from there :smile:
  6. Jun 28, 2011 #5


    User Avatar
    Science Advisor

    It would be better to write this as -5n- 2= -2n- 26

    So combine the two: add 2n to both sides, add 2 to both sides

    (If you don't like negatives, you could start by multiplying both sides by -1 to get
    5n+ 2= 2n+ 26. Now subtract 2n from both sides, subtract from both sides.)
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook