## When adding and subtracting rational algebraic expressions which of the following steps should you do first?

- Step 1: Combine the numerators together.
- Step 2: Put the sum or difference found in step 1 over the common denominator.
- Step 3: Reduce to lowest terms as shown in Tutorial 32: Multiplying and Dividing Rational Expressions.
- Step 1: Combine the numerators together.

**How adding and subtracting fractions is similar to adding and subtracting rational expressions?**

We can add and subtract rational expressions in much the same way as we add and subtract numerical fractions. To add or subtract two numerical fractions with the same denominator, we simply add or subtract the numerators, and write the result over the common denominator.

**How will you compare subtraction of rational expressions with subtraction of rational expressions?**

When the denominators are the same, you subtract the numerators and place the difference over the common denominator. To subtract rational expressions, subtract the numerators and place the difference over the common denominator.

### Which of the following should be determined when adding and subtracting rational expressions with different denominators?

Find the Least Common Denominator of Rational Expressions When we add or subtract rational expressions with unlike denominators we will need to get common denominators.

**How do you find the least common denominator when adding and subtracting rational expressions?**

To find the LCD of two rational expressions, we factor the expressions and multiply all of the distinct factors. For instance, if the factored denominators were (x+3)(x+4) ( x + 3 ) ( x + 4 ) and (x+4)(x+5) ( x + 4 ) ( x + 5 ) , then the LCD would be (x+3)(x+4)(x+5) ( x + 3 ) ( x + 4 ) ( x + 5 ) .

**How do you solve rational expressions?**

The steps to solving a rational equation are:

- Find the common denominator.
- Multiply everything by the common denominator.
- Simplify.
- Check the answer(s) to make sure there isn’t an extraneous solution.