Answer
(a.) $\$22,000$
(b.) $\$21,809$ Reasonably well.
(c.) $\$21,726$ Reasonably well.
Work Step by Step
(a.) In the graph Consider the point $(2010,22)$on the line graph.
It indicates in $2010$ the cost is $22$ thousands of dollars.
$=\$22,000$.
(b.) The given model
$\Rightarrow C=442x+12,969$
Plug $x=2010-1990=20$.
$\Rightarrow C=442(20)+12,969$
Simplify.
$\Rightarrow C=442(20)+12,969$
$\Rightarrow C=8840+12,969$
$\Rightarrow C=\$21,809$
Reasonably well.
(c.) The given model is
$\Rightarrow C=2x^2+390x+13,126$
Plug $x=2010-1990=20$.
$\Rightarrow C=2(20)^2+390(20)+13,126$
Simplify.
$\Rightarrow C=2(20)^2+390(20)+13,126$
$\Rightarrow C=800+7800+13,126$
$\Rightarrow C=\$21,726$
Reasonably well.
