<PRE><B>Question 749651</B>
when is it necessary to find the least common denominator of two rational expressions? 
Ans: when you are adding or subtracting fractions with different denominators.
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Describe the process for finding the LCD of two rational expressions. 
Example:
3/8 + 5/10
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To find the lcd:
8 = 2^3
10 = 2*5
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lcd must contain each of the prime factors is its highest power
lcd = 2^3*5 = 8*5 = 40
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Rewrite each fraction with the lcd as its denominator:
(3/8) = (3/8)(5/5) = 15/40
(5/10 = (5/10)(4/4) = 20/40
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Add the equivalent fractions that have the same denominator to get:
= 35/40
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How is factoring related to this process?
Comment: See the example.
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Cheers,
Stan H.
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