Question

The 6th term of an AP is -6 and the 10th term is -26 find the 15th term of the AP

Answer 1

Answer:

The fifteenth term of the A.P is -51

Step-by-step explanation:

In an A.P,

t6 = a + 5d = -6

t10 = a + 9d = -26

By using elimination method,

d = -5

a = 19

So the fifteenth term,

t15 = a + 14d

= 19 - 70

= -51

Answer 2

Answer:

Given,

a6 = -6

a10 = -26

a15 = ?

a15 = a+14d

a + 5d = -6

a + 9d = -26

solving simultaneously,

-4d = 20

d = -5

substitute the value of d in any one of the equations.

a + 5(-5) = -6

a - 25 = -6

a = -6 + 25

a = 19

Now,

a15 = 19 + 14(-5)

a15 = 19 - 70

a15 = -51

Hope this helps you☺