Répondre :
1.
c = d/(a+b)
ac + bc = d => bc = d - ac => b = (d - ac)/c
2.
vt = x - x0 => v = (x - x0)/t
c = d/(a+b)
ac + bc = d => bc = d - ac => b = (d - ac)/c
2.
vt = x - x0 => v = (x - x0)/t