Question

if 2(a^2+b^2)=(a+b)^2 then show that a=b

Answer 1

$2 {a}^{2} + 2 {b}^{2} = {a}^{2} + {b}^{2} + 2ab$
${a}^{2} + {b}^{2} - 2ab = 0$
${(a - b)}^{2} = 0$
$a - b = 0$
$a = b$