If x - y = 7 and xy = 9, find the value of x2+y2

1.	If x - y = 7 and xy = 9, find the value of x2+y2
Answer» Given that, x – y = 7 Squaring both sides, we get (x – y)²= (7)² x² + y² – 2xy = 49 Its given that xy = 9, x² + y² – 2 (9) = 49 x² + y² = 49 + 18 x² + y² = 67

Answer»

Given that, x – y = 7

Squaring both sides, we get

(x – y)²= (7)²

x² + y² – 2xy = 49

Its given that xy = 9,

x² + y² – 2 (9) = 49

x² + y² = 49 + 18

x² + y² = 67

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