Product <em /><em /><em>is the answer to a multiplication problem.
Multiple is the product of the number and whole numbers.
Hopefully this helps! :D :D
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Selections 2, 3, 5, 6 are polynomials.
1 and 4 are not. The coefficients don't have to be integers, but the powers of the variables need to be positive integers. In 1, you have x^-1. in 4, you have x^(1/2).
The expression x-4 will come out to be a negative integer. That means X <em>has to be </em>something that when 4 is taken away from it, the answer is still negative.
Let's try 5.
5-4 is 1. Is 1 negative? No, so that doesn't work.
4-4 is 0. 0 isn't negative either, so that doesn't work.
3-4 is -1. Is -1 negative? YES! Let's try it for 2 as well, just to be safe.
2-4 is -2. Still negative.
X can be anything less than 4.
He spent exactly 20.25, so it's A.