If x and y are integers greater than 1, is x a multiple of y?
(1) 3y^2 +7y = x
(2) x^2 - x is a multiple of y
Thanks,
Cappy
Is x a multiple of y?
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IMO A.
statement 1 can be written as
y(3y + 7) = x
means y times some integer ( 3y + 7 will be an integer because x, y are intergers) is X
hence x is a multiple of y.
statement 2 can be written as
x( x-1) = y
will be sufficient only id x is a multiple of y.
but in this case there are 3 options.
x is a multiple of y
x-1 is a multiple of y
and both X and x-1 arent the multiple of y.
hence insufficient
hope it helps...
statement 1 can be written as
y(3y + 7) = x
means y times some integer ( 3y + 7 will be an integer because x, y are intergers) is X
hence x is a multiple of y.
statement 2 can be written as
x( x-1) = y
will be sufficient only id x is a multiple of y.
but in this case there are 3 options.
x is a multiple of y
x-1 is a multiple of y
and both X and x-1 arent the multiple of y.
hence insufficient
hope it helps...
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to clarify the second stat.:
x^2 - x is a multiple of y
=>
x^2 - x = ky
=>
x(x-1) = ky
=>
x/y = k/(x-1) : which k/(x-1) can be integer and cannot be integer.
=> answer is A.
x^2 - x is a multiple of y
=>
x^2 - x = ky
=>
x(x-1) = ky
=>
x/y = k/(x-1) : which k/(x-1) can be integer and cannot be integer.
=> answer is A.