Explanation

A rational expression is a fraction where the numerator and/or denominator are polynomials.

Example:
(2x² − 4x) / (6x)

To reduce a rational expression:

1. Factor the numerator

2. Factor the denominator

3. Cancel common factors

Example:
(2x(x − 2)) / (6x)
Cancel 2x:

= (x − 2) / 3

Important:

• You can only cancel factors, not terms.

• Values that make the denominator 0 are not allowed.

Quiz (5 Questions)

1. What is a rational expression?

2. Factor the numerator of x² − 9.

3. Reduce (x² − 9)/(x − 3).

4. Can you cancel x from x + x²?

5. Why must the denominator never be 0?

Answer Key

1. A ratio of polynomials

2. (x − 3)(x + 3)

3. x + 3

4. No

5. Division by zero is undefined