Question

the sum of three numbers in an ap is 15 and sum of their squares is 147 find them

Answer 1

hope this is the answer

Answer 2

Let a-d, a, a+d are three terms in AP

Sum of three terms = 15

a- d+ a + a+d =15

⇒3a=15

a=15/3

a= 5

Sum of the squares of the extremes = 147

(a-d) ² +a² + (a+d) ²= 147

⇒(5-d) ² +5² + (5+d)² =147

⇒75 +2d²=147

⇒2d² = 147-75

⇒d² = 72/2

∴d²=6

Therefore, the required three terms are

If a=5 , d= 6          

a-d = -1

a = 5

a+d = 11