Explanation

To add or subtract rational expressions:

1. Find a common denominator

2. Rewrite each expression

3. Combine numerators

4. Simplify

Example:
1/x + 1/(x + 1)

Common denominator: x(x + 1)

= (x + 1 + x) / x(x + 1)

Quiz

1. What is required before adding fractions?

2. What stays the same when adding?

3. Can denominators be added directly?

4. Why do we use a common denominator?

5. What is the final step?

Answer Key

1. Common denominator

2. Denominator

3. No

4. To combine numerators

5. Simplify