Resposta :
Temos que:
S = So + vt
Sa = 150 - 35t
Sb = 0 + 15t
***************************
Sa = Sb
150 - 35t = 0 + 15t
150 = 15t + 35t
150 = 50t
150/50 = t
*******************
t = 3 segundos
*******************
S = So + vt
Sa = 150 - 35t
Sb = 0 + 15t
***************************
Sa = Sb
150 - 35t = 0 + 15t
150 = 15t + 35t
150 = 50t
150/50 = t
*******************
t = 3 segundos
*******************