The sum of two numbers is 17and the sum of their squares is 157.Find the numbers.
Answers
Answered by
19
let the no. be x and (17-x)
so acc to your question
x+(17-x) = 17
x sq+(17-x) sq=157
x sq +289+x sq -34x = 157
2x sa +289-157-34x =0 so by applying the factorization method u will get two values of x
one is positive and other is negative so we will prefer the positive one ...
hope it will help you
so acc to your question
x+(17-x) = 17
x sq+(17-x) sq=157
x sq +289+x sq -34x = 157
2x sa +289-157-34x =0 so by applying the factorization method u will get two values of x
one is positive and other is negative so we will prefer the positive one ...
hope it will help you
Answered by
15
Heya..
I'm here to help you..
Let two numbers be x and y.
According to question,
=) x + y = 17
And
(x^2 + y^2) = 157
=) (x+y) = 17
Squaring both sides,
=) (x+y) ^2 = 17^2
=) x^2 + y^2 + 2xy = 289
=) 157 + 2xy = 289
=) 2xy = 289 - 157
=) 2xy = 132
=) xy = 132/2
=) xy = 66
-------------------
Since (x-y) ^2 = x^2 + y^2 - 2xy
= 157 - 2(66)
= 157 - 132
= 25
Hence (x-y) = 5.....
At last we get two equations,
=) x+y = 17 and
x-y = 5
-------------
Add both equations,
=) x+ y + x - y = 17 + 5
=) 2x = 22
=) x = 22/2
=) x = 11..
Put its value to find y.
=) x-y = 5
=) 11 - y = 5
=) 11-5 = y
=) 6 = y..
Hence x = 11 and y = 36.
Hope it's helpful to u.
I'm here to help you..
Let two numbers be x and y.
According to question,
=) x + y = 17
And
(x^2 + y^2) = 157
=) (x+y) = 17
Squaring both sides,
=) (x+y) ^2 = 17^2
=) x^2 + y^2 + 2xy = 289
=) 157 + 2xy = 289
=) 2xy = 289 - 157
=) 2xy = 132
=) xy = 132/2
=) xy = 66
-------------------
Since (x-y) ^2 = x^2 + y^2 - 2xy
= 157 - 2(66)
= 157 - 132
= 25
Hence (x-y) = 5.....
At last we get two equations,
=) x+y = 17 and
x-y = 5
-------------
Add both equations,
=) x+ y + x - y = 17 + 5
=) 2x = 22
=) x = 22/2
=) x = 11..
Put its value to find y.
=) x-y = 5
=) 11 - y = 5
=) 11-5 = y
=) 6 = y..
Hence x = 11 and y = 36.
Hope it's helpful to u.
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