Answer:
assume it is 1
Step-by-step explanation:
If no information is given that would help you define 'a', you may assume it is 1.
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Information about the y-intercept will constitute a given point, and let you compute a value for 'a'. The direction of opening, and/or the end behavior will tell you the sign of 'a', but (alone) is non-specific as to its value. A description of the polynomial as "monic" tells you the value of 'a' is 1.
