The sum of square of 2 consecutive odd natural numbers is394. Then the value of smaller number is?
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Answers
Answer:
Given :-
- The sum square of 2 consecutive odd natural numbers is 394.
To Find :-
- What is the smaller number.
Solution :-
Let,
➦ First Number = x
➦ Second Number = x + 2
According to the question,
↦ x² + (x + 2)² = 394
↦ x² + x² + 2(x)(2) + (2)² = 394 [ (a + b)² = a² + 2ab + b² ]
↦ x² + x² + 4x + 4 = 394
↦ 2x² + 4x + 4 - 394 = 0
↦ 2x² + 4x - 390 = 0
↦ 2(x² + 2x - 195) = 0
↦ x² + 2x - 195 = 0 × 2
↦ x² + 2x - 195 = 0
↦ x² + (15 - 13)x - 195 = 0
↦ x² + 15x - 13x - 195 = 0
↦ x(x + 15) - 13(x + 15) = 9
↦ (x + 15)(x - 13) = 0
↦ (x + 15) = 0
↦ x + 15 = 0
➠ x = - 15
↦ (x - 13) = 0
↦ x - 13 = 0
➠ x = 13
We can't take x as negative (- ve)
So, the x is 13.
Hence, the required numbers are :
❒ First Number :
⇒ First Number = x
➲ First Number = 13
❒ Second Number :
⇒ Second Number = x + 2
⇒ Second Number = 13 + 2
➲ Second Number = 15
∴ The smaller number is 13.
Step-by-step explanation:
♧♧Given:-
- The sum of square of 2 consecutive odd natural number is 394.
♧♧To prove:-
- The value of smaller number
♧♧Proof:-
♡♡Lets take ,
- First number should be x
- Second number should be x+2
♧♧From the question ,
- x^2+(x+2)^2=394.
- x^2+x^2+2 (x)(2)+(2)^2=394
●(a+b)^2=a^2+b^2+2ab)
- x^2+x^2+4x+4=394
- 2x^2+4x+4-394=0
- 2x^2+4x+390=0
- 2 (x^2+2x+2-195)=0
- x^2+2x-195=0×2
- x^2+2x-195=0
- x^2+15x-13x-195=0
- x (x+15)-13 (x+15)=0
- x+15=0 x-13=0
- x=-15 x=+13
♧♧We will not take x as negative so ,
- The number is 13.
♧♧According to the question,
- First number=13
- Second number =x+2
=13+2=15.