Answer:
$7.76
Explanation:
So you can express the price in the slope-intercept form: y=mx+b where m is the slope, but in this context it's the price per km, and b is the y-intercept, but in this context it's the base price (how much it costs even if the length is 0 km)
So it gives you the slope of $0.22 per km. so you now have the equation
y = 0.22x + b
To find the base amount or y-intercept, you can take some of the given points, the price will be y, and the length will be x.
I'll use the point (6, 4.68)
Plugging these values into the equation you get:
4.68 = 0.22(6) + b
multiply
subtract 1.32 from both sides
So now we have the full equation:
y = 0.22x + 3.36
Now to find the price if the length is 20km, simply plug in 20 as x
y = 0.22(20) + 3.36
Multiply
y = 4.4 + 3.36
Add
y=7.76