How to Multiply Fractions with Variables
When multiplying fractions, I am a fan of factorizing and canceling common factors instead of multiplying and then simplifying.
The reason for this is that it makes the calculations much easier, and I like it when things are easy. By cross-canceling when possible instead of expanding the parentheses, the calculations become simpler and less messy.
Here you will learn to multiply fractions with variables by factorizing and cross-canceling. Beware that you can only cancel factors that are on both sides of the fraction bar.
Multiplication Through Canceling
- 1.
- Factorize the numerators.
- 2.
- Factorize the denominators.
- 3.
- Cancel common factors.
- 4.
- Find the answer.
Evaluate
You factorize and cross-cancel in this way:
Evaluate
You factorize using the third algebraic identity of quadratic expressions, and then you cancel and multiply like this:
Evaluate
Use the third algebraic identity of quadratic expressions to factorize, and then cross-cancel and multiply in this manner:
Evaluate
You factorize with the help of the third algebraic identity of quadratic expressions, and then you cancel and multiply the fractions in this way: