Question

if four times the fourth term of an ap is equal to 7 times its 7th term find its 11th term​

Answer 1

4(a_4) = 7(a_7)

4(a + 3d) = 7(a + 6d)

4a + 12d = 7a + 42d

7a - 4a + 42d - 12d = 0

3a + 30d = 0

3(a + 10d) = 0

a + 10d = 0

a_11 = 0