## ← Add Rational Expressions Practice 1 - Visualizing Algebra

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Showing Revision 2 created 05/24/2016 by Udacity Robot.

1. We find the lowest common denominator by factoring each of these denominators
2. first. The first denominator will have factors of x plus 2 times x minus 6,
3. since factors of 12 that sum to negative 4 are positive 2 and negative 6. The
4. factors for x squared minus 36 would be x minus 6 and x plus 6. This is just the
5. difference of two perfect squares. We can see that both of the denominators
6. share a common factor of x minus 6. So this is the factor they share, and we
7. list it in the middle. The other factor of this denominator is x plus 2, and the
8. other factor of this denominator is x plus 6. Finally, we just multiply all
9. these factors together to get our lowest common denominator, right here.