Which quadratic function best fits this data?
1 answer:
The data has a peak at x=5, so we expect it to be modeled with a parabola that opens downward. That is the x² coefficient will be negative.
For x=1, the third choice gives a better approximation to (x, y) = (1, 32) than does the first choice. It is appropriate to choose
... y = -11.41x²+154.42x-143.9
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The quadratic regression function of a graphing calculator confirms this choice.
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