Theory:

When performing operations with monomials as fractions, the mathematical transformations are the same as in common fractions.  
Example:
Add the monomials 5x2y4+7x2y4 
1) Add the expressions in the numerators.
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2) If possible, reduce the numeric factors of the numerator and the denominator.
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Example:
Subtract the monomials a4b282a4b23
1) Make denominators the same.
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2) Subtract the expressions in the numerators.
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This fraction cannot be simplified.
Example:
Multiply the monomials 7m32mn5 
1) When multiplying the fractions, multiply the numerators and multiply the denominators.
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2) Multiply the variables by adding their exponents. Remember: if the exponent of a variable factor is not specified, then it is \(1\).
 
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