Q14 of 95 Page 93

If x + y = 12 and xy = 14, find the value of (x2 + y2).

Given,


x + y = 12


Let’s square the both sides,


We get;


= (x + y)2 = (12)2


= x2 + y2 + 2xy = 144


= x2 + y2 = 144 – 2xy


Also given,


xy = 14


= x2 + y2 = 144 – 2(14)


= x2 + y2 = 144 – 28


= x2 + y2 = 116


So, the value of (x2 + y2) is 116.


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