A team of scientists is traveling by boat to study a pod, or group, of dolphins. The equation y = 0.2x can be used to find the distance, y, in miles the boat travels in x minutes. The dolphins are currently 8.4 mi from the boat. If the dolphins stay to where they are, how long will it take the boat to reach them? Show your work.

42 minutes.

Step-by-step explanation:

We know that:

y = 0.2*x

is the equation that that defines the distance, in miles, that the boat travels in x minutes.

We know that the dolphins are at 8.4 miles from the boat.

Then when we have y = 8.4, this will mean that the boat reached the dolphins.

Then we need to solve the equation:

y = 8.4 = 0.2*x

for x

To do that, we just need to isolate x in one side of the equation, so we can just divide both sides by 0.2 to get:

8.4/0.2 = (0.2*x)/0.2

42 = x

And x is time in minutes, thus, the boat needs to travel for 42 minutes to reach the dolphins.