For what it's worth, it's not as if you have to solve EVERY problem in under two minutes. That's just the average. This is a particularly difficult 700+ question!
s1: put a= 0 and b =5 then the cirlce touches y axis but if the center is 3, 8 then the cirlce never touches y axis so, not sufficient![:)]( "Smile")
s2: this clearly shows, a is not equat to 0 so, it never touches y axis so sufficient.
but took more than 2 minutes to solve![:(]( "Sad")
![:(]( "Sad")
[/quote]
s1: put a= 0 and b =5 then the cirlce touches y axis but if the center is 3, 8 then the cirlce never touches y axis so, not sufficient
s2: this clearly shows, a is not equat to 0 so, it never touches y axis so sufficient.
but took more than 2 minutes to solve
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