coordinate

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coordinate

by sud21 » Thu Jan 12, 2012 4:51 am
In the xy-plane, line A has slope a and line B has slope b. Are the two lines parallel to each other?
1). 4^a=2^b
2). 2^a=3^b

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by neelgandham » Thu Jan 12, 2012 10:56 am
In the xy-plane, line A has slope a and line B has slope b. Are the two lines parallel to each other? . can be rephrased to Is a = b ?
1). 4^a=2^b
2^2a = 2^b
Implies 2a = b,
If a = 0, b = 0, ab = 0
If a = 1, b = 2, ab = 2
If a = 2, b = 4, ab = 8.. Insufficient to answer the question Is a = b ?
2). 2^a=3^b
a=0 and b=0 is the only solution set. Hence sufficient!

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Anil Gandham
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