Final answer:
To simplify the given expression and cancel 'D', we factor out a common factor of D/2 from both terms and simplify step-by-step. The simplified expression, after canceling 'D', is D/2 - √(D^2 + xD).
Step-by-step explanation:
To simplify the expression and cancel 'D', we can factor out a common factor of D/2 from both terms.
d = √((x+ D/2)^2 + y^2) - √((x^2+ D/2)^2 + y^2)
Let's simplify the expression step-by-step: