Respuesta :

SvetkaChem

Answer:

- 8 m/s

Explanation:

average velocity = Δx /Δt = [x2 - x1] /[t2 - t1]

t2 = 2 sec, t1 = 0 sec

x2 = x(2) = 20 - 4 * 2² = 20 - 16 = 4 m

x1 = x(1) = 20 - 4*0² = 20 m

average velocity = Δx /Δt = [4 m - 20 m] /[2 s - 0 s] = - 16 m/ 2 s= - 8 m/s