Problem:
1) If x is an integer and y=3x+2, which of the following cannot be a divisor of y?
A) 4
B) 5
C) 6
D) 7
E) 8
The official ans. explanation states that "Altough 3x is always divisible by 3, so 3x+2 cannot be div. by 3 since 2 is not divisible by 3. Thus, 3x+2 cannot be divisible by any multiple of 3, including 6." Though by that logic can't the test taker think to himself, well 2 cannot be divisble by 7 as well.
Brain is fried and perhaps I can't see the obvious here. Any help is much appreciated!
Thanks
1) If x is an integer and y=3x+2, which of the following cannot be a divisor of y?
A) 4
B) 5
C) 6
D) 7
E) 8
The official ans. explanation states that "Altough 3x is always divisible by 3, so 3x+2 cannot be div. by 3 since 2 is not divisible by 3. Thus, 3x+2 cannot be divisible by any multiple of 3, including 6." Though by that logic can't the test taker think to himself, well 2 cannot be divisble by 7 as well.
Brain is fried and perhaps I can't see the obvious here. Any help is much appreciated!
Thanks
