Algebra-1

Let's expand each of the given formulas using the formula (a - b)² = a² - 2ab + b²:

For option A:
a = 8x, b = 4y
then, (8x - 4y)² = (8x)² - 2(8x)(4y) + (4y)² = 64x² - 64xy + 16y².

For option B:
a = 8x, b = 2y
then, (8x - 2y)² = (8x)² - 2(8x)(2y) + (2y)² = 64x² - 32xy + 4y².

For option C:
a = 4x, b = 4y
then, (4x - 4y)²