Given in the question:
a.) The first costs $5 upfront and $4 per kilometer.
b.) The second costs $15 plus $3 per kilometer.
Let's generate the equation of each of the car service charges,
Let,
y = total cost of service
x = distance traveled
a.) The first costs $5 upfront and $4 per kilometer.
[tex]\text{ y = 5 + 4x}[/tex]
b.) The second costs $15 plus $3 per kilometer.
[tex]\text{ y = 15 + 3x}[/tex]
Let's determine the driving distance when the two companies charge the same.
We get,
[tex]y_{1st\text{ Company}}=y_{2nd\text{ Company}}_{}[/tex][tex]\text{ 5 + 4x = 15 + 3x}[/tex][tex]\text{ 4x - 3x = 15 - 5}[/tex][tex]\text{ x = 10}[/tex]
Therefore, the two companies charge the same at a driving distance of 10 kilometers.
Summary:
1. The system of equations.
y = 5 + 4x
y = 15 + 3x
2. The solution.
x = 10
3. Graphing the system of equations.