The answer is: " 9a² + 7a " .
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Note: (3a)² + 7a = (3a)*(3a) + 7a = 9a² + 7a .
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1. You divide by 100 to find the decimal version of any percentage, and do the opposite for vise versa
Looks like the answer would be 219 people since you can't have half a person.
Evaluate the function at the three values of the range and see what you get. The appropriate choice is ...
... D) {15, 3, 0}
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Evaluation can sometimes be simpler if you rearrange the function to a form called "Horner's form."
... f(x) = (x -4)x +3
Then the evaluation looks like (for x=-2) ...
... f(-2) = (-2-4)(-2)+3 = (-6)(-2) +3 = 12 +3 = 15
This is sufficient to identify D as the answer of choice.