SLO

Latex Test

If x – y = 2 and x^{2}+y^{2}=20 , Then what would be the value of (x+y)^{2} :
[A]38
[B]36
[C]16
[D]12

36
\because \left ( x-y \right )^{2}=x^{2}+y^{2}-2xy
=> 2^{2}=20-2xy
=> 2xy=20-4=16..............(1)
\therefore (x+y)^{2}=x^{2}+y^{2}+2xy
= 20 + 16 = 36
So option (B) is the right answer.

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