Answer:
Graph A = 20miles/gallon
Graph B = 20
Step-by-step explanation:
For graph A, to find the change you will need to choose two points from the graph (the easier the better)
So for example, I've chosen 40miles-2gallons (2, 40) and point 0 (0, 0)
Now you will need to remember the slope formula which is:
so your point (x1, y1) will be (0, 0)
and point (x2, y2) will be (2, 40)
so
which is
and so you get that the slope will be 20 miles/gallon
For graph B, what they want you to see is that change of y/change of x means the same as change of miles/change of gallons since x is the gallons and y is the miles.