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What is the equation in standard form of a parabola that models the values in the table

X -2. 0. 4

F(x) 2.5 1.5 -60.5


A

B

C

D

What is the equation in standard form of a parabola that models the values in the-example-1
User Andrbrue
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1 Answer

6 votes

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Answer:

(b) y = -2.5x² -5.5x +1.5

Explanation:

The table entry (0, 1.5) tells you that the y-intercept is 1.5. That eliminates choices C and D.

Substituting x=4 into the first equation (choice A) shows you it is incorrect:

y = -5.5(4²) -2.5(4) +1.5 = -88 -10 +1.5 = -96.5 . . . not -60.5

This only leaves choice B, a choice confirmed by a quadratic regression using a graphing calculator (or spreadsheet).

y = -2.5x² -5.5x +1.5

What is the equation in standard form of a parabola that models the values in the-example-1
User Jack Zach Tibbles
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