Given that, a3​=4, a9​=−8We know that,an​=a+(n−1)da3​=a+(3−1)d4=a+2d ... (i)Anda9​=a+(9−1)d−8=a+8d ... (ii)On subtracting equation (i) from (ii), we get,−12=6dd=−2From equation (i), we get,4=a+2(−2)⇒a=8Let nth term of this A.P. be zero.an​=a+(n−1)d0=8+(n−1)(−2)⇒n=5 Hence, 5th term of this A.P. is 0.