4.9 Graph and Solve Quadratic Inequalities Name: ______________
Objectives: Students will be able to solve quadratic inequalities
using graphs and sign charts.
For what x values is the graph equal to 0?
Greater than 0?
Less than 0?
-3
4
Nov 10­2:51 PM
Examples: Solve the inequality by graphing. Label the
x-intercepts and the vertex clearly.
1.) x2 + 8x + 7 < 0
Nov 10­6:11 PM
1
Examples: Solve the inequality algebraically. (SIGN CHART)
1.) x2 - 11x + 28 > 0
Nov 10­6:13 PM
2.) 3x2 + 1 < 15x
Nov 10­6:28 PM
2
Name: _______________
ICE PARTNER:
Solve. One partner will solve by graphing. The other partner will
solve algebraically. Then, reverse roles for the second problem.
1.) x2 + 6x + 5 < 0
Nov 10­6:29 PM
2.) x2 -2x > 8
Oct 21­6:44 PM
3
4.9 Homework
Solve by graphing.
1.) x2 - 6x - 7 > 0
Name: _______________
2.) x2 + 4x < -4
Oct 21­6:45 PM
Solve using sign charts.
3.) x2 -6x - 16 < 0
4.) 2x2 +7x > -5
Oct 21­6:48 PM
4