Problem Solving

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Problem Solving

by vladmire » Sun Nov 02, 2008 10:19 am
What type of question is this? Looks like foil method should be used but I'm still getting lost

If a = 1 and b = -2, then (2a^2 + b)(x + y) + (a + b)(x-y) =

0
2x
y-x
x-y
x+y
Source: — Problem Solving |

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by moonlite » Sun Nov 02, 2008 10:52 am
I pluged in the values for a and b and got C as the answer
what is the OA?

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by Nidhi Jain » Sun Nov 02, 2008 10:56 am
My calculations says Y-X i.e. C.
What is OA?

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2nd set of terms

by vladmire » Sun Nov 02, 2008 11:29 am
answer is c, but how do I work out the second set of terms? (1+2)(x-y)?

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Re: Problem Solving

by stop@800 » Sun Nov 02, 2008 11:59 am
vladmire wrote:What type of question is this? Looks like foil method should be used but I'm still getting lost
What is this fiol method??
If a = 1 and b = -2, then (2a^2 + b)(x + y) + (a + b)(x-y) =

0
2x
y-x
x-y
x+y

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Re: Problem Solving

by dmateer25 » Sun Nov 02, 2008 12:03 pm
stop@800 wrote:
vladmire wrote:What type of question is this? Looks like foil method should be used but I'm still getting lost
What is this fiol method??
If a = 1 and b = -2, then (2a^2 + b)(x + y) + (a + b)(x-y) =

0
2x
y-x
x-y
x+y
First, Inner, Outer, Last

You know how to do it, maybe just never heard it referred to as that. Here is an example:

(x+2)(x+3)
x^2 + 2x + 3x + 6

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by cramya » Sun Nov 02, 2008 12:04 pm
Stop@800, Foil is just kaplan's stratgey of how we should mutliply 2 terms for eg

(a+b) (a-b). Its nothing more than that.



answer is c, but how do I work out the second set of terms? (1+2)(x-y)?
This should be (1-2) (x-y) which will make it y-x[/quote]