Question

Given the table of values, complete the table for the quadratic equation y = - 6x? + 3x + 8 to find the values of the high or low point of the
parabola.
This table shows the corresponding values of x and y, with some missing values for y.
Steps: -1, -0.75, -0.5, -0.25, 0, 0,25, 0.5, 0.75, 1
Solution: -1, 2.375, 5, __, 8, 8.375, __, __, 5
Which of the following is correct?
(1 point)
(0.25, 8.375) is the low point on the parabola.
(0.5,9) is the high point on the parabola.
(0.25, 8.375) is the high point on the parabola.
(-1, - 1) is the low point on the parabola.

Answer 1

Complete y-values: -1, 2.375, 5, 6.875, 8, 8.375, 8, 6.875, 5.

Vertex: x = -b/(2a) = -3/(2·-6) = 0.25. y(0.25) = -6(0.25)^2 + 3(0.25) + 8 = 8.375. Since a = -6 < 0 the parabola opens down, so this is the high point.

Correct choice: (0.25, 8.375) is the high point on the parabola.