The sum of the squares of two consecutive odd numbers is 394. Find the numbers
Answers
Answer:
13 and 15 ..........................
Step-by-step explanation:
Given:-
The sum of the squares of two consecutive odd numbers is 394.
To find:-
Find the numbers
Solution:-
The general form of an odd is 2n+1
Let the two consecutive numbers be 2n+1 and 2n+3.
Their squares are (2n+1)² and (2n+3)²
Their sum =(2n+1)² +(2n+3)²
(a+b)²=a²+2ab+b²)
=>[(2n)²+2(2n)(1)+(1)²]+[(2n)²+2(2n)(3)+(3)²]
=>4n²+4n+1+4n²+12n+9
=>8n²+16n+10
According to the given problem
Their sum =394
=>8n²+16n+10=394
=>8n²+16n+10-394=0
=>8n²+16n-384=0
=>8(n²+2n-48)=0
=>n²+2n-48=0/8
=>n²+2n-48=0
=>n²+8n-6n-48=0
=>n(n+8)-6(n+8)=0
=>(n+8)(n-6)=0
=>n+8=0 or n-6=0
=>n=-8 or n=6
If n=-8 then 2n+1=>2(-8)+1=-16+1=-15
and 2n+3=2(-8)+3=-16+3=-13
If n=6 then 2n+1=2(6)+1=12+1=13
and 2n+3=2(6)+3=12+3=15
Answer:-
The required cosecutive odd numbers are 13 and 15
(If given they are positive)