Part A:
The equation in standard form is given Ax+By+C = 0
where x is the gradient of a straight line (or the rate of change)
The rate of change = (113-43) / (8-3) = 70/5 = 14
This value means there's an increase of $14 for every hour rented.
We also need to work out the value of C, which is the fixed value (happen at x=0)
We know that Amir paid $43 for 3 hours.
Amir would have paid $29 for 2 hours
Amir would have paid $15 for 1 hour
Since the hourly rate is $14, the fixed fee is 15 - 14 = $1
The equation that represents the total cost of renting a scooter is
y = 14x + 1
Rearranging this equation to get the standard form
14x - y + 1 = 0
Part B:
Writing the equation as function ⇒ f(x) = 14x + 1
Part C:
To graph the equation, we can start by choosing the x-intervals, say we have the value of x between 0 and 10
x 0 1 2 3 4 5 6 7 8 9 10
y 1 15 29 43 57 71 85 99 113 127 141
Each pair of x-value and y-value is then plotted on a graph then each plot is joined to draw a straight line.