Data Sufficiency

In the xy plane, the line k passes through origin and through the point (a,b), where ab is not equal to zero.
Is b positive?

1.) The slope of the line k is negative.

2.) a<b

(i) negative slope-- two possibilities--- Line can be in Q 2 or Q4 i.e ( -a,+b) or (+a,-b)-- not a definite answer-INSUFF

(ii) a<b- can have many possible points.- INSUFF

When combined,

we have (-a,+b) satisfying both conditions. .

b is not Negative.

SUFFICIENT to answer.

C

Let me know if i did a blunder...