9514 1404 393
Answer:
-20
Explanation:
Put 3 where x is and do the arithmetic.
f(3) = -2·3² +3 -5
f(3) = -2·9 +3 -5 = -18 +3 -5 = -15 -5
f(3) = -20
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Sometimes it is easier to evaluate polynomials when they are written in Horner form:
f(x) = (-2x +1)x -5
f(3) = (-2·3 +1)(3) -5 = -5(3) -5 = -20