Question

Find the 10th term of ap sum of the 3rd term and 8th term is 7 and some of the 7th term and 14th term is–3​

Answer 1

Answer:

a10 = -1

Step-by-step explanation:

a3 + a8 = 7

a + 2d + a + 7d = 7

2a + 9d = 7...(1)

and,

a7 + a14 = -3

a + 6d + a + 13d = -3

2a + 19d = -3

using elimination method,

19d - 9d = -3 -7

10d = -10

d = -1

putting d in eq 1

2a = 7 + 9

a = 16/2

a = 8

and now, a10 = a + 9d

a10 = 8 - 9

a10 = -1