Q11 of 116 Page 6

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

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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