Final answer:
An equation that describes a friend who is running towards you at a constant speed.
Step-by-step explanation:
To write an equation that describes a friend who is 70 feet away and running towards you at a constant speed of 3ft/s, we can use the equation:
distance = initial distance + speed * time
Let's represent the initial distance as 'd', the speed as 's', and the time as 't'. Plugging in the values, we get:
distance = 70ft + 3ft/s * t
This equation describes the distance covered by the friend as a function of time.