Re: If x is an integer and y = 3x + 2, which of the following
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18 Sep 2020, 14:32
This problem can be solved by listing different values of y, and quickly eliminating choices.
y = 3x + 2. In other words, y = (any multiple of 3) + 2. This gives us the values 5 (which is 3*1 + 2), 8, 11, 14, 17, 20 and so on.
Looking at this list we can eliminate the answers 4 (a divisor of 8), 5 (divisor of 20), 7 (divisor of 14), and 8 (divisor of 8). This leaves us with 6, C as the answer. This answer makes sense because 6 is the only answer that's a multiple of 3, and if you add only 2 to any multiple of 3, the resulting number (5, 8, 11, ...) will never be a multiple of three, or of 6.