If 2^x - 2^(x-2) = 3(2^13), what is the value of x?
a. 9
b. 11
c. 13
d. 15
e. 17
Please explain
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Exponent problem - help!
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vasbli
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2^x - 2^(x-2) = 3(2^13)
1. Factorization by 2^(x-2) as it is the highest factor of 2^x - 2^(x-2)
(2^2-1)x2^(x-2)=3(2^13)
3x2^(x-2)=3(2^13), ie by dividing by 3 each side of equation
2^(x-2)=2^13
hence x-2=13
x=15
D
1. Factorization by 2^(x-2) as it is the highest factor of 2^x - 2^(x-2)
(2^2-1)x2^(x-2)=3(2^13)
3x2^(x-2)=3(2^13), ie by dividing by 3 each side of equation
2^(x-2)=2^13
hence x-2=13
x=15
D
