Not sure how to do this one. please help! thanks.
If x and y are positive integers, what is the value of x + y?
(1) (2^x)(3^y) = 72
(2) (2^x)(2^y) = 32
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Is it D?kookoo4tofu wrote:Not sure how to do this one. please help! thanks.
If x and y are positive integers, what is the value of x + y?
(1) (2^x)(3^y) = 72
(2) (2^x)(2^y) = 32
1 - sufficient. 2^x*3^y = 2^3*3^2 = 72. Therefore x+y = 3+2
2 - sufficient. 2^(x+y) = 2^5. x+y = 5
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Yep - break down the right sides of the equations to have the same bases!
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