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: Brain fart algebra question.

  1. Feb 2, 2010 #1
    I know this is a dumb question but dumb questions are easier to fix than dumb mistakes so here goes.

    Is 2x(x)= 3x

    or 2x(x) = 2x^2
     
  2. jcsd
  3. Feb 2, 2010 #2
    2x^2
     
  4. Feb 2, 2010 #3

    Mark44

    Staff: Mentor

    2x(x) means 2*x*x, which can be written as 2x2, as Tevion stated. This could also be written as 2xx, but is usually not written that way.

    In algebraic expressions, multiplication is not usually shown explicitly, while addition (and subtraction and division) always are shown explicitly. If two expressions are next to each other, with or without parentheses, the two expressions are understood to be multiplied.

    2xy = 2*x*y.
    3xy + 2x = 3*x*y + 2*x.
    3(xy + 2x) = 3*(xy + 2x) = 3xy + 6x.
    2x + x = x(2 + 1) = x(3) = 3x
     
  5. Feb 2, 2010 #4

    HallsofIvy

    User Avatar
    Science Advisor

    2x+ x= 3x
     
  6. Feb 2, 2010 #5
    thanks everybody
     
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook