Answer: (A) [tex]y = 0.55x + 5.5[/tex]
Step-by-step explanation:
Let m be the fixed rate charged by Kevin and n be the fixed delivery fee.
Equation for total charge: [tex]y=mx+n[/tex] , where y is the amount of money ( in dollars) Kevin will charge when he makes a trip of x miles to deliver groceries.
Then, the system of equation for the given descriptions will be :-
[tex]10m+n=11----------(1)\\\\ 5m+n=8.25----------(2)[/tex]
Subtract equation (2) from equation (1), we get
[tex]5m=2.75[/tex]
Divide both sides by 5 , we get
[tex]m=0.55[/tex]
Put m= 0.55 in (2), we get
[tex]5(0.55)+n=8.25\\\\ 2.75+n=8.25\\\\ n=8.25-2.75=5.5[/tex]
Now, the equation could be used to determine the amount of money (y), in dollars, Kevin will charge when he makes a trip of x miles to deliver groceries will be :
[tex]y = 0.55x + 5.5[/tex]