Question

If x+y=5,xy=1, Then x²+y² is​

Answer 1

$x + y = 5 \\ xy = 1$

${(x + y)}^{2} = {x}^{2} + 2xy + {y}^{2} \\ {(5)}^{2} = {x}^{2} + {y}^{2} + 2 \times 1 \\ 25 = {x}^{2} + {y}^{2} + 2 \\ {x}^{2} + {y}^{2} = 25 - 2 \\ {x}^{2} + {y}^{2} = 23$