Use the information on page 314 to explain how you can find the time a trampolinist spends above a certain height.

1. Writing in MathUse the information on page 314 to explain how you can find the time atrampolinist spends above a certain height. Include a quadratic inequality that describes the timethe performer spends more than 10 feet above the ground, and two approaches to solving thisquadratic inequality. Quadratic Inequalities
Main Ideas
• Graph quadratic
inequalities in two
variables.
• Solve quadratic
inequalities in one
variable
.
GET READY for the Lesson
Californian Jennifer Parilla is the only
athlete from the United States to
qualify for and compete in the
Olympic trampoline event.
Suppose the height h(t) in feet of a
trampolinist above the ground
during one bounce is modeled by
the quadratic function
h(t) = -16+2 +42+ + 3.75. We can
solve a quadratic inequality to
determine how long this performer
is more than a certain distance above
the ground
New Vocabulary
quadratic inequality
Graph Quadratic Inequalities You can graph quadratic inequalities in
two variables using the same techniques you used to graph linear
inequalities in two variables.
Step 1 Graph the related quadratic
function, y = ax + bx + c. Decide
if the parabola should be solid
or dashed
M
sor
Step 2 Test a point (x,y) inside the parabola.
Check to see if this point is a solution of
the inequality.
o
V, 30(X) + b(x) + C
Step 3 If (x,yı) is a solution, shade the
region inside the parabola. If (x,y)
is not a solution, shade the region
outside the parabola.
11:
(* 1,V) is
a solution.
(*1Y) is not
a solution
294 Chapter 5 Quadratic Functions and inequalities
GB