Question

plz tell the formal solution

Answer 1

${x}^{2} + {y}^{2}$
this is an identity
hope it belps
pls mark me as brainliest

Answer 2

$(x + y)(x - y) \\ x(x - y) + y(x - y) \\ x {}^{2} - xy + xy - y {}^{2} \\ x {}^{2} - y {}^{2}$
Hope it will help you