ardz24 wrote:If a and b are non-negative integers, ab=?
1) 9^a=3^b
2) 5^a=2^b
Statement 1: 9^a = 3^b
(3²)^a = 3^b
3^(2a) = 3^b.
Since the bases are equal, the exponents must also be equal.
Thus:
2a = b.
If a=0, then b = 2*0 = 0, with the result that ab = 0*0 = 0.
If a=1, then b = 2*1 = 2, with the result that ab = 1*2 = 2.
Since ab can be different values, INSUFFICIENT.
Statement 2: 5^a = 2^b
The equation above is valid only if a=0 and b=0.
Thus, ab = 0*0 = 0.
SUFFICIENT.
The correct answer is
B.
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