Step-by-step explanation
Since Brian drives at a constant speed, in order to get the rate, we need to compute the slope, by applying the slope equation, as shown as follows:
Where (x_1,y_1)=(20,100) (x_2,y_2)= (50,140)
Plugging in the terms into the slope equation:
In conclusion, the distance will increase by 4 miles per hour.