# Multiplying Rational Expressions

###### Recommendation

### Want a study guide too?

Multiplying rational expressions is as easy as adding the exponents and simplifying. Ta da!

Algebra | Rewrite rational expressions |

Algebra II | Polynomials and Rational Expressions |

Language | English Language |

Mathematics and Statistics Assessment | Rational and Exponential Expressions, Equations, and Functions |

Polynomials and Rational Expressions | Factoring |

### Transcript

Their dilemma is represented by the following...

4 x over 5 y squared times 20 x-squared y over y to the fourth.

Now let's talk about what they have in common.

Remember, usually when we multiply fractions, we multiply across top and bottom.

But when we see a chance, we can simplify first by canceling any duplicate factors.

Looking at our problem, we can see that the 20 in the top of the second fraction

and the 5 in the bottom of the first fraction are both factors of 5.

We can simplify by dividing 20 by 5 to get 4,

and divide the 5 on the bottom by 5 to get 1.

Looking at the second fraction, we can cancel the top y with the y to the fourth on the bottom...

leaving y to the power of three.

Now we can just multiply across the top of the two fractions...

4 x times 4 x-squared equals 16 x-cubed.

And multiply across the bottom... y-squared times y-cubed...

...remember that we multiply two terms with the same base, and we can add the two exponents...

in this case, the 2 and 3, to get y to the fifth.

So the answer is 16 x cubed over y to the power of 5.

And on the space station orbiting Jupiter, this result means that it's Xavier's turn

to take out the plutonium.

Don't forget to shut the airlock.