Question

x^2 + y^2 +xy = 1 and x+y = 2 then find xy.​

Answer 1

Answer:

${x}^{2} + {y}^{2} + xy = 1 \\ adding \: xy \: both \: sides \\ {x}^{2} + {y}^{2} + xy + xy= 1 + xy\\ {x}^{2} + {y}^{2} + 2xy = 1 + xy\\( {x + y})^{2} = 1 + xy \\ {2}^{2} = 1 + xy \\ 4 = 1 + xy \\ 4 - 1 = xy \\ 3 = xy$