Question

i need to know how adding and subtracting rational expressions is similar to adding and subtracting simple fractions and how they are different

Answer 1

For starters, both rational expressions and simple fractions are best added or subtracted when the least common denominator (LCD) has been identified and every rational expression and/or fraction has been modified to involve the same denominator.

In combining rational expressions, we're likely to have polynomial expressions in the numerators that are easier to combine when expanded using the distributive property. Simple fractions don't require this step; one simply combines the integer numerators as appropriate.