Answer
(a) 59 dollars
(b) 180 miles
(c) 300 miles
(d) The implied diomain is $[0,\infty)$
Work Step by Step
(a) Calculate C(40):
$C(40)=0.35(40)+45$
$C(40)=14+45$
$C(40)=59$ dollars
(b) Replace C(x) for 108 and solve for x:
$108=0.35x+45$
$108-45=0.35x+45-45$
$63=0.35x$
$63/0.35=0.35x/0.35$
$x=180$ miles
(c) Replace C(x) for 150 and solve for x:
$150=0.35x+45$
$150-45=0.35x+45-45$
$105=0.35x$
$105/0.35=0.35x/0.35$
$x=300$ miles
(d) Since the negative miles can't be driven, we count from zero, and, theoretically, one could drive forever. So the domain is $[0,\infty)$
