Question

the the sum of three number in AP is 9 and the sum of their square is 59 find the number ​

Answer 1

Step-by-step explanation:

consider a+b, a, a-b are three numbers in AP

their sum is 9

a-b+a+a+b=9

3a=9

a=3;

sum of their squares is 59

(a-b) ²+a²+(a+b)²=59

3a²+2b²=59

3(3²)+2b²=59

2b²=59-27

2b²=32

b=4;

then

a-b=3-4=-1

a=3

a+b=3+4=7

Therefore the three numbers in AP are -1,3and 7