Algebra-1

To expand and simplify (xy − 2mn) (xy + 2mn), we can use the formula for multiplying binomials:

(a + b)(a - b) = a² - b²

In this case, a is xy and b is 2mn. Substituting these values into the formula, we get:

(xy − 2mn) (xy + 2mn) = (xy)² - (2mn)²
                   = x²y² - 4m²n²