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why is this so hard to me today

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why is this so hard to me today

by resilient » Tue Feb 05, 2008 6:24 pm
2^4 *2^5 / 2^7-2^4 = ?


I get 2^9/2^3= 2^6

what did i do wrong?












qa is -12
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solution

by tutonaranjo » Tue Feb 05, 2008 7:30 pm
hey... you can't subtract exponents with the same base.
All you could do is factor out like this

2^4 *2^5 / 2^7-2^4 =

2^9/2^4(2^3 - 1) = (factored 2^4 in the denominator)

2^5/(2^3 - 1) = you can only subtract exponents when they are divided
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by sibbineni » Wed Feb 06, 2008 3:58 am
I think the question is

(2^4*2^5/2^7)-2^4

(2^9/2^7)-2^4

2^2-2^4

4-16

=-12
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