Question

13. The 7 th term of an AP is -4 and its13th term is -16.Find the AP.​

Answer 1

Answer:

-2is the answer

Step-by-step explanation:

f1+6d= -4

f7+6d= -16

-4+6d= -16

6d= -16+4= -12

d= -12/6= -2

AP=8, 6, 4, 2, 0, -2, -4, -6, -8, -10, -12, -14, -16..........

Answer 2

Given - The 7th term of an AP is - 4 and 13th term is

- 16

To find - The AP

Solution -

Let,the AP be a, a+d, a+2d,a+3d,a+4d,a+5d,a+6d,a+7d,a+8d,a+9d,a+10d,a+11d,a+12d...

Let, the first term be a and the common difference be d

a+6d= - 4

a= - 4-6d......1)

a+12d= - 16

-4-6d+12d = - 16[By 1)]

-4+6d= - 16

6d= - 16+4

6d = - 12

d = - 12/6

d = - 2

Now,substituting the value of d in 1)

a= - 4-6d

a = - 4-6(-2)

a= - 4+12

a = 8

Therefore the AP-

8,6,4,2,0,-2,-4,-6,-8,-10,-12,-14,-16....