Is it multiple choice? An example would be 2, 8, 32...
<span>a whole number between 42.3 and 43.1 = 43
so answer
</span><span>q = 43.0</span>
There is more than one solution because there are two different numbers whose square is 9. One of them is +3. The other is -3.
The fundamental theorem of algebra says every non-zero single-variable polynomial of degree N has exactly N roots, counting multiplicity. Your polynomial is degree 2, so has 2 roots.