Question

Does the quadratic have a maximum or minimum

vertex, and does the parabola open up or down?

A)max/ opens up
B)max/ opens down
C)min/ opens up
D)min/ opens down

Answer 1

B)max/ opens down

Explanation:

Parabola equation:

The equation of a parabola has the following format:

`y = ax^2 + bx + c`

If
`a > 0`, that is, x² is multiplied by a positive number, the function has a minimum value and the parabola opens up.

If
`a < 0`, that is, x² is multiplied by a negative number, the function has a maximum value and the parabola opens down.

In this question:

`y = -x^2 - 2x + 3`

From the graph, we already see that it opens down and has a max, and analitically, since
`a = -1 < 0`, this is confirmed. The correct answer is given by option b.