Answer! !
a taxi charges $1.50 plus a fee of $0.60 for each mile traveled. if a ride cost $5.40, how many miles was the ride?
the taxi miles.

Looks like we have enough information to make an equation! Since the $0.60 per mile is a flat and constant rate, this equation would take the form of a line and thus we can use the slope-intercept formula:

y = mx + b where

So let's list out what we know:
The taxi will always charge a base rate of $1.50. That means b = 1.50. If you were looking at this on a graph, that is the point where the line crosses the y-axis (since you can't have a negative value ride!). 
You are charged $0.60 per mile. That means m = 0.60 and x = miles.
And finally, we know the ride is $5.40 overall! That would be our y.

So let's plug it all in

5.40 = 0.60x + 1.50
We can find out how many miles were driven by solving for x
First, let's subtract 1.50 from both sides

5.40 - 1.50 = 0.60x + 1.50 - 1.50
3.90 = 0.60x
Now divide both sides by 0.60 to isolate x

3.90/0.60 = 0.60x/0.60
6.5 = x

Since x = miles, we know that the taxi drove 6.5 miles!

Not enough information