Which of the following situations represents a linear relationship

Question

a) a train travels 45 miles every hour after departing the station

b) the area covered by a circular eat tug depends on the radius of the rug

c) the value of a car is decreasing by 7 percent each year

d)the number of bacteria in a lab experiment tripled every hour

Answer 1

train travels 45 miles every hour is a linear relationship

Answer 2

Hello! A linear relationship means that a change in one part will consistently cause the same change on the other part. If you were to draw a graph, this would be a straight diagonal line. We know that anything that happens the exponent of something produces an exponential graph. Therefore, we know that the correct answer must be a because the train will move at a continued speed and the distance it will have traveled will increase proportional to the speed and time it has traveled.