Starting from 100 ft away, your friend skates toward you and then passes you. She skates at a constant speed of 20 ft/s. Her distance d from you in feet after t seconds is given by d.= l100-20tl At what times is she 40 ft from you?
To find the times when your friend is 40 ft from you, we substitute d = 40 into the given equation:
40 = 100 - 20t
Rearranging the equation to solve for t:
20t = 100 - 40
20t = 60
t = 60/20
t = 3 seconds
So, your friend is 40 ft from you at 3 seconds.
To find the times when your friend is 40 ft away from you, we need to solve the given equation for d = 40. Let's plug in the values and solve for t.
d = 100 - 20t
Setting d = 40, we have:
40 = 100 - 20t
Now, let's solve this equation for t:
20t = 100 - 40
20t = 60
Dividing both sides by 20, we get:
t = 60/20
t = 3
Therefore, your friend is 40 ft away from you after 3 seconds.
To find the times when your friend is 40 ft from you, we can set up the equation:
40 = 100 - 20t
Rearranging the equation, we get:
20t = 60
Dividing both sides by 20, we have:
t = 3
Therefore, your friend is 40 ft from you at t = 3 seconds.