simplify: 2v512x^2y^3 - xyv50y and explain please

Question

Can you please explain

Answer 1

2√(512x^2y^3) - xy√(50y)

= 2√(2*16^2X^2Y^3)-xy√(2*5^2Y)                       Split the 512 into 2*16^2 and 50 into 2*5^2

=(2*16*X*Y)√(2*Y)-5xy√(2y)                                Take all the values having ^2 outside the √

=32xy√(2Y)-5xy√(2y)                                            Take xy√2y as common factor

=(XY√2y)(32-5)

=27xy√2y