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## Algebra (all content)

### Unit 13: Lesson 2

Simplifying rational expressions- Reducing rational expressions to lowest terms
- Reducing rational expressions to lowest terms
- Simplifying rational expressions: common monomial factors
- Reduce rational expressions to lowest terms: Error analysis
- Simplifying rational expressions: common binomial factors
- Simplifying rational expressions: opposite common binomial factors
- Simplifying rational expressions (advanced)
- Reduce rational expressions to lowest terms
- Simplifying rational expressions: grouping
- Simplifying rational expressions: higher degree terms
- Simplifying rational expressions: two variables
- Simplify rational expressions (advanced)
- Simplifying rational expressions (old video)

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# Simplifying rational expressions (old video)

CCSS.Math:

Sal simplifies (28b^6)/(7b) as 4b^5. Created by Sal Khan and Monterey Institute for Technology and Education.

## Video transcript

Simplify the expression 28b
to the sixth divided by 7b. Well this is the same
thing as 28/7 times b to the sixth over b. And I did it this
way so that we have b to the sixth over b
to some other power. And this is over b, which is the
same thing as b to the first. So we could simplify this
using exponent properties. And 28/7 we can just
clearly simplify because 28 is divisible by 7. 28 divided by 7 is just 4. So that is just 4. And then b to the
sixth divided by b to the one, that's just going
to be b to the sixth minus 1 power. So times b to the sixth
minus 1 or b to the fifth. So our answer is
4b to the fifth.