Question

If x+y=7 and xy=3,find the value of x and y

Answer 1

$On \: squaring \: both \: sides \\ \\ {(x + y)}^{2} = {7}^{2} \\ \\ {x}^{2} + {y}^{2} + 2xy = 49 \\ \\ {x}^{2} + {y}^{2} + 2 \times 3 = 49 \\ \\ {x}^{2} + {y}^{2} + 6 = 49 \\ \\ {x}^{2} + {y}^{2} = 49 - 6 \\ \\ {x}^{2} + {y}^{2} = 43$

Answer 2

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