Answer: Choice D
The plus/minus of the following: 1/2, 1, 2, 5/2, 4, 5, 10, 20
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Explanation:
Refer to the rational root theorem. To find the possible rational roots, we divide the factors of the last term 20 over the factors of the first coefficient 2.
- Factors of 20 are: 1,2,4,5,10,20
- Factors of 2 are: 1,2
Dividing those said factors leads us to the list in choice D. We include the positive and negative versions of each result. For example, divide 10 over 2 to get 10/2 = 5 as one possible root (which leads to -5 as well).
A table like the one shown below might be handy to keep track of all the terms.
