Algebra 1 help. Please solve this?

Question

(a - b) /( a + b) -( a + b) / (a - b)

Answer 1

Given statement is (a - b) /( a + b) -( a + b) / (a - b)

= (a - b) /( a + b) -( a + b) / (a - b)

Lcm of a + b and a - b is a² - b²

= [(a - b)(a - b) - ( a + b)( a + b)] / a² - b²

= [(a - b)² - ( a + b)²] / a² - b²

= [a² - 2ab + b² - a² - 2ab + b²] / a² - b²

= - 4ab  / a² - b²

The simplified expression is  - 4ab  / a² - b²

Answer 2

Given statement is (a - b) /( a + b) -( a + b) / (a - b)

= (a - b) /( a + b) -( a + b) / (a - b)

Lcm of a + b and a - b is a² - b²

= [(a - b)(a - b) - ( a + b)( a + b)] / a² - b²

= [(a - b)² - ( a + b)²] / a² - b²

= [a² - 2ab + b² - a² - 2ab - b²] / a² - b²

= - 4ab  / a² - b²

The simplified expression is  - 4ab  / a² - b²