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Im Stuck and Need Your Help

So ive been trying this problem for close to two hours and still can't come to a conclusion, and some help would be nice. So basil here we go :

btw....
^= the following number is an expontent
*= multiplication

2^2010 - 2^2009 - 2^2008 + 2^2007 = k * 2^2007

what is the value of K.
So mathletes give it your best shot and see if you can provide some support. Sorry for wasting your time, even if you just read the problem and thanks for all the help.
-Sincerely,
me

February 11, 2013

10 Comments • Newest first

deathmaker21

Yea,, I'll just stick to my Financial math... Annuity, bond's and loans that are interrupted with varying interest rates are so much easier to do that whatever this is

[i]And i thought going to college for accounting was boring looking[/i] >.>

Reply February 12, 2013
good341

k= 2^2008
because 2^2010 is 2(2^2009) and 2^2009= 2(2^2008) etc...

Reply February 12, 2013 - edited
magegurl13

isnt this like, sequences and series.

Reply February 11, 2013 - edited
Archfiendz

@Eaglesmash56:
well either:
do it by hand which would probably take a bit
find online calculator with no number cap if thats even possible
or I think there is a way to subtract exponents but I did that so long ago I don't remember exactly what to do.

Reply February 11, 2013 - edited
Eaglesmash56

[quote=iSeekMen]k= 2^2008?

EDIT: terrible explanation but 2^2010- 2^2009= 2^2009
2^2009-2^2008= 2^2008
@2^2008 + 2^2007 / 2^2007= k
the 2^2007's cancel out so you get 2^2008... unless im just bsing[/quote]

oh my god i think its gonna work out because i tried it on a lower level as in 2^4 - 2^3 and i got 8 which is equivalent to 2^3.
P.S. my girlfriend says she loves you because shes in the same class and she needed the answer too xD

Reply February 11, 2013 - edited
crazymaster

k = 3 (I think)

2^2010 - 2^2009 - 2^2008 + 2^2007 = k * 2^2007
Split them up so they all have a common factor.
(2^3 * 2^2007) - (2^2 * 2^2007) - (2^1 * 2^2007) + (1 * 2^2007) = k * 2^2007
Factor out the 2^2007.
2^2007 * (2^3 - 2^2 - 2^1 + 1) = k * 2^2007
Divide 2^2007 out from both sides and combine the terms in the bracket.
8 - 4 - 2 + 1 = k
k = 3

Reply February 11, 2013 - edited
Eaglesmash56

[quote=Archfiendz]well to lazy to grab a clac but that seems REALLY easy. just multiply out the exponents subtract and add that last one. divide your answer by 2^2007 to get K.
As far as my Algebraic skills go that seems like the route to go...

EDIT: meant calc[/quote]

I tried that but the calculator i used provided by my schoo (Ti-84) gets an overload error because 2^2010 exceeds the number cap.

Reply February 11, 2013 - edited
Archfiendz

well to lazy to grab a clac but that seems REALLY easy. just multiply out the exponents subtract and add that last one. divide your answer by 2^2007 to get K.
As far as my Algebraic skills go that seems like the route to go...

EDIT: meant calc

Reply February 11, 2013 - edited
zpattack12

Wrong section bud.

Reply February 11, 2013 - edited