Répondre :
Bonsoir,
t = 5n-1
t0 = 5*0-1 = -1
t1 = 5 - 1 = 4
t2 = 10 - 1 =9
-n + 15 = 87
=> -n = 87-15 = 72
=> n = -72
t = 5n-1
t0 = 5*0-1 = -1
t1 = 5 - 1 = 4
t2 = 10 - 1 =9
-n + 15 = 87
=> -n = 87-15 = 72
=> n = -72