x is a multiple of y if y * some integer k = x

x = k*y

Stmt I

3y^2 + 7y = x

x = y(3y+7)

Since y is an integer 3y+7 is an integer = k

x = y * k

SUFF

Stmt II

x^2-x is a multiple of y

x ( x-1) = y * k

Either x is a mutiple of y or x-1 is a amultiple of y

INSUFF

Eg:

x=5 x-1=4 y=2 k=10 NO

x=4 x-1=3 y=2 k=6 YES

Choose A)

couldnt get ur 2nd statement cramya...pls elbaorate

factor x out x( x-1) = y * k


Examples:
x=5 x-1=4 y=2 k=10 NO x is not a multiple of y

x=4 x-1=3 y=2 k=6 YES x is a multiple of y


Vivek,
If u could please post the ds questions in the ds forum.

Friendly suggestion: Almost all problems(especially gmat prep) u have posted has been solved on this forum. If u use the search function u can find solutions to all wihtout having to wait for a response.

Good luck!

Regards,
Cramya