Question

if a=x+y and b=x-y ,show that (a-b)^2=4y^2​

Answer 1

Step-by-step explanation:

$((x + y) - (x - y) ){}^{2} = 4 {y}^{2}$

$(2y) {}^{2} = 4 {y}^{2}$

${2}^{2} {y}^{2} = {4y}^{2}$

$4 {y}^{2} = 4 {y}^{2}$