To understand the concept and procedure for
dividing
monomials
it is suggested that you first
review the lesson on multiplying monomials.

  Multiplying monomials is a two step process.
First the coefficients of each monomial are
multiplied as you would multiply any
two or more numbers.
And secondly, you follow the rules for
multiplying variables,
whether the variables are like or unlike.

 

For example:

(5a)(-2b) = -10ab
or...
(3x3)(2x2) = 6x3+2 = 6x5
and finally...
(2c2d)(3c4d2)(-5c4d3) = -30c10d6

In division we follow the same two step process.
However, because multiplication and division are
inverse (opposite) operations, instead of
multiplying the coefficients of the monomials
 we must divide them.
And secondly we must follow the rules for dividing variables,
which means that when dividing like variables we must subtract the exponents instead of adding them.
The best way to understand this is to
look at some examples...

Example #1

(14x4)÷(2x2) = ?
First...divide the coefficients:  14÷2 = 7
Second...divide the variables: x4÷x2 = x4-2 = x2
So the answer is:
(14x4)÷(2x2) = 7x2

Example #2

(-32x5y4)÷(-4x2y3) = ?
First...divide the coefficients: -32÷-4 = 8
Second...divide the variables: x5y4÷x2y3 = x5-2y4-3 = x3y
So the answer is:
(-32x5y4)÷(-4x2y3) = 8x3y

(-32x5y4)÷(-4x2y3) = ?
First...divide the coefficients: -32÷-4 = 8
Second...divide the variables: x5y4÷x2y3 = x5-2y4-3 = x3y
So the answer is:
(-32x5y4)÷(-4x2y3) = 8x3y
 

Example #3
In this example we will see what happens when we divide monomials
which do not have like variables.

(-12x3)÷(4y2) = ?
First...divide the coefficients: -12÷4 = -3
Second...if the variables are not like then the best we can
do is to leave them as a fraction:
x3÷y2 = x3/y2
So the answer is:
(-12x3)÷(4y2) = -3x3/y2

 

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