Answer:
Domain = [tex]\{x|x\geq 0\}[/tex]
Range = [tex]\{y|y\geq 20\}[/tex]
Step-by-step explanation:
We are given,
The cost of the phone bill is represented by the function,
[tex]C(m) =0.05m+20[/tex], where m = number of minutes used.
Now, as 'm' is the number of minutes used. So, they cannot be negative.
Thus, the domain of the function is [tex]\{x|x\geq 0\}[/tex].
Further, when m= 0, then [tex]C(0) =0.05\times 0+20[/tex] i.e. C(0)= 20.
Thus, the range of the function is [tex]\{y|y\geq 20\}[/tex].
