If (x-y)=4 and xy= 12, the value of x×x + y×y is

1.	If (x-y)=4 and xy= 12, the value of x×x + y×y is
Answer» Answer is 28 Solution:-x-y=4Squaring on both sides,(X×X)-(Y×Y)=4{Use the formula of a square minus b square}x×x+y×y-2×X×Y=4x×x+y×y-2×XY=4( now value of xy=12 so,) x×x+y×y-2×12=4x×x+y×y-24=4( now bring -24 into RHS side so it will become positive 24) x×x+y×y=4+24x×x+y×y=28

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