Factorization of the square of 25X + 40x (Y-X) + 16 (X-Y)

Factorization of the square of 25X + 40x (Y-X) + 16 (X-Y)

25x²+40x(y-x)+16(x-y)²
25x²-40x(x-y)+16(x-y)²
=[5x-4(x-y)]²
=(x+4y)²