Question

Evaluate (2x+y) (2x-y)

Answer 1

${(2x})^{2} - {y}^{2} \\ = 4 {x}^{2} - {y}^{2}$
am I right?

Answer 2

=(2x)(2x)-(2x)(y)+(y)(2x)-(y)^2

=4x^2 - 2xy + 2xy - y^2 =4x^2 - y^2