If x+y = 4 and xy = 2, find the value of x2+y2

1.	If x+y = 4 and xy = 2, find the value of x2+y2
Answer» Given that, x + y = 4 and xy = 2 We take the equation: x + y = 4 and on squaring both sides, we get (x + y)² = 4² x² + y² + 2xy = 16 x² + y² + 2(2) = 16 (Because xy = 2 is given) x² + y² + 4 = 16 x² + y² = 16 – 4 x² + y² = 12 Therefore, the value of x² + y² is 12

Answer»

Given that,

x + y = 4 and xy = 2

We take the equation: x + y = 4 and on squaring both sides, we get

(x + y)² = 4²

x² + y² + 2xy = 16

x² + y² + 2(2) = 16 (Because xy = 2 is given)

x² + y² + 4 = 16

x² + y² = 16 – 4

x² + y² = 12

Therefore, the value of x² + y² is 12

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