Page 599 - Algebra 1

Find any x-intercepts and the maximum or minimum of the parabola y = x2 - x - 2.
5. Entertheequationy=x2 -x-2intothe Y= editor.
6. Press 6:ZStandard to graph the equation.
7. Use the keystrokes in Step 4 to find the coordinates of the two
x-intercepts.
The x-intercepts of the parabola are (-1, 0) and (2, 0).
8. Find the minimum of the parabola. Press and select 3:minimum.
Use the key to trace along the curve to
a point on the left of the minimum and then press . Press the key to trace along the curve to a point to the right of the minimum and then press . Press the key to trace to
a point near the minimum and then press .
The approximate coordinates appear at the bottom of the screen. Decimal values may vary slightly. The minimum of the parabola occurs at about the point (0.5, -2.25).
This parabola has three distinct characteristic points: two x-intercepts–or zeros–and one minimum.
Lab Practice
a. Graph the parabola y = x2 - 2x - 3. Find any x-intercepts and the maximum or minimum of the parabola.
b. Graph the parabola y = -x2 - x + 6. Find any x-intercepts and the maximum or minimum of the parabola.
584 Saxon Algebra 1