Question

Which point is an x-intercept of the quadratic function f(x)=(x-8)(x+9)?

Answer 1

`Answer: \\ (x - 8)(x + 9) = 0 \\ \Leftrightarrow x = 8 \: \vee \: x = - 9 \\ \Rightarrow ( - 9,0)`

Answer 2

For this case we want to know the x-intercept points of the following quadratic function:

The interdection points of the parabola with the x axis are obtained by making
`y = 0`.

`f (x) = (x-8) (x + 9)`

We have:

`x-8 = 0\\x = 8`

First point:

(8,0)

So we have:

`x + 9 = 0\\x = -9`

Second point:

(-9,0)

ANswer:

Option D