Find two consecutive positive integers, sum of whose squares is 365.

AcademicMathematicsNCERTClass 10

Given:

Two consecutive numbers whose squares have the sum 365. 

To do:

We have to find the two numbers.

Solution:

Let the two consecutive numbers be $x$ and $x+1$.

This implies,

$x^2+(x+1)^2=365$

$x^2+x^2+2x+1=365$    (Since $(a+b)^2=a^2+2ab+b^2$)

$2x^2+2x+1-365=0$

$2x^2+2x-364=0$

$2(x^2+x-182)=0$

$x^2+x-182=0$

Solving for $x$ by factorization method, we get,

$x^2+14x-13x-182=0$

$x(x+14)-13(x+14)=0$

$(x+14)(x-13)=0$

$x+14=0$ or $x-13=0$

$x=-14$ or $x=13$

If $x=13$, $x+1=13+1=14$

The two consecutive positive integers are $13$ and $14$.

raja
Updated on 10-Oct-2022 13:20:12

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