Graphing Quadratic Equations: example 10.46

Find the intercepts of the parabola $y = x^{2} - 2 x - 8$ .

Work it out on paper first. Then open the solution one step at a time, and stop as soon as you can finish on your own.

Your turn

The book's Try It right after this example: same idea, new numbers. Only the answer is given.

Find the intercepts of the parabola $y = x^{2} + 2 x - 8 .$

How did it go?


To find the y-intercept, let $x = 0$ and solve for y.
		When $x = 0$ , then $y = −8$ . The y-intercept is the point $(0, −8)$ .

To find the x-intercept, let $y = 0$ and solve for x.
Solve by factoring.


To find the y-intercept, let $x = 0$ and solve for y.
		When $x = 0$ , then $y = −8$ . The y-intercept is the point $(0, −8)$ .

To find the x-intercept, let $y = 0$ and solve for x.
Solve by factoring.