Question

a=-18 d=? n=10 an= 0 find d

Answer 1

an = a+(n-1)d
0 = - 18 +(10-1)d
18 = 9d
d = 18/9
d=2

Answer 2

Given,

a = -18, n = 10 and an =0

To find,

The value of d.

Solution,

In an arithmetic progression we know that an = a + (n-1)d

• an is defined as an nth term of an Arithmetic Progression, n is the number of terms in Arithmetic Progression and d is a common difference between the terms in an Arithmetic Progression.

⇒   an = a + (n-1)d

⇒   0 = -18 + (10-1)d

-18 will be shifted from the Right-Hand  Side of the equation to Left Hand Side of the equation and its sign would change from -18 to + 18.

Therefore we get,

⇒   18 = 9d

⇒   d = 2.

Hence the value of common difference d is 2.