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Math Help - factoring help

  1. #1
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    factoring help

    How do you solve (5a+3)2-10a2-6a? Which method is used for this?
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  2. #2
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    Quote Originally Posted by sinjid9 View Post
    How do you solve (5a+3)^2-10a^2-6a? Which method is used for this?
    in future, use the caret symbol (^) to denote exponents.



    "factoring" the expression (not "solving") ...

    (5a+3)^2 - 10a^2 - 6a<br />

    (5a+3)^2 - 2a(5a + 3)

    (5a+3)[(5a+3) - 2a]

    (5a+3)(3a+3)

    3(5a+3)(a+1)
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  3. #3
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    Quote Originally Posted by sinjid9 View Post
    How do you solve (5a+3)2-10a2-6a? Which method is used for this?
    If you mean solve : (5a+3)^2 - 10a^2 - 6a = 0 ; then:
    25a^2 + 30a + 9 - 10a^2 - 6a = 0
    15a^2 + 24a + 9 = 0
    Now solve for x using the quadratic formula.; you'll get 2 solutions.
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  4. #4
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    why does the -2a go into the bracket?
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  5. #5
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    Because it is being multiplied by the 1st term (5a + 3)

    Try understanding this:
    (5a + 3)^2 - 2a(5a + 3)
    Let x = 5a + 3 ; then:
    x^2 - 2ax
    x(x - 2a) : kapish?
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  6. #6
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    Then whats considered a complex trinomial 3(a+b)-a+b or a(3+b)-a+b
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  8. #8
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    Ok... but in a(3+b)-a+b does the coefficient of a in the first term affect whether it is a complex trinomial or not, or does it depend on what numbers are in the brackets?
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  9. #9
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    Quote Originally Posted by sinjid9 View Post
    Ok... but in a(3+b)-a+b does the coefficient of a in the first term affect whether it is a complex trinomial or not, or does it depend on what numbers are in the brackets?
    What are you asking? a(3 + b) - a + b = 2a + 4b , that's it.
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  10. #10
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    Which one of these is a complex trinomial
    a(3 + b) - a + b or 3(a+b)-a+b
    or are they both complex trinomials?
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  11. #11
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    Are you fooling around?
    Neither is a trinomial.

    Trinomial - Wikipedia, the free encyclopedia
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