If x2 + y2 = 29 and xy = 10, where x > 0, y > 0, x

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If x² + y² = 29 and xy = 10, where x > 0, y > 0, x > y
then the value of x + y is
x − y

x² + y² = 29;
xy = 10
∴ (x + y)² = x² + y² + 2xy
= 29 + 2 × 10 = 49
⇒ x + y = ±7
Again, (x – y)² = x² + y² – 2xy
= 29 – 2 × 10 = 9
∴ x – y = ±3

∴	x + y	=	±7	=	7
	x – y		±3		3

then the value of	x + y	is
	x − y