1. ## Functions and graphs

Question: If f(x) = -1, what is x? what point(s) are on the graph of f?

f(x) = 2x^2 -x -1

Is x 0? How am I suppose to get the points? :/

2. Originally Posted by cokeclassic
Question: If f(x) = -1, what is x? what point(s) are on the graph of f?

f(x) = 2x^2 -x -1

Is x 0? How am I suppose to get the points? :/
$2x^2 - x - 1 = -1$

$2x^2 - x = 0$

$x(2x - 1) = 0$

$x = 0$ and $x = \frac{1}{2}$

so, the points on the graph where f(x) = -1 are (0, -1) and (1/2, -1)

3. thanks