Chapter 3.1, Problem 114E

(a)

To determine

To calculate: Quadratic equation to express the number of homicides y as a function of x using quadratic regression in a graphing calculator, where x is the number of years after 1994.

Year	Homicides per 100,00
$1994$	$9.0$
$1996$	$7.4$
$1998$	$6.3$
$2000$	$5.5$
$2002$	$5.6$
$2004$	$5.5$
$2006$	$5.7$
$2008$	$5.4$
$2010$	$4.8$

(b)

To determine

To graph: Quadratic function $y=0.0219x^2-0.551x+8.552$ that expresses the number of homicides per 100,000 population and to plot the data in the given table.

(c)

To determine

To calculate: The year when the number of homicides $y=0.0219x^2-0.551x+8.552$ will be minimum, where x is the number of years after 1994.

(d)

To determine

To calculate: The year when the number of homicides $y=0.0219x^2-0.551x+8.552$ will again be 6.3 homicides per 100,000 population, where x is the number of years after 1994.