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If $x + y = 7$ and $x y = 12$ , find $x^{2} + y^{2}$ .

Class 9Algebraic IdentitiesPolynomials

A73
B37
C25
D49

Step-by-Step Solution

x^{2} + y^{2} = (x + y)^{2} - 2 x y = 49 - 24 = 25

. (37 subtracts

x y

only once; 73 adds

2 x y .

)

Answer: C) 25

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