Which of the following statements is NOT true regarding simplifying rational
expressions?
When dividing one rational expression by another rational expression, you can rewrite your
expression as a multiplication problem.
When multiplying two rational expressions together, you must first have a common denominator.
When adding two rational expressions together, you must first have a common denominator.
When multiplying two rational expressions together, the numerators get multiplied together
while the denominators get multiplied together,

The statement which is not true regarding simplifying the rational expression is When multiplying two rational expressions together, you must first have a common denominator.

We have to determine, which of the following statements is NOT true regarding simplifying rational  expressions?

According to the question,

Let, the first rational number be x,

and another rational number be y,

The statement which is not true regarding simplifying the rational expression is given in the steps given below to follow all the steps given below.

1. When dividing one rational expression by another rational expression, you can rewrite your expression as a multiplication problem is,

2. When multiplying two rational expressions together, you must first have a common denominator.

3. When adding two rational expressions together, you must first have a common denominator.

4. When multiplying two rational expressions together, the numerators get multiplied together  while the denominators get multiplied together,

Hence, The statement which is not true regarding simplifying the rational expression is When multiplying two rational expressions together, you must first have a common denominator.

For more details refer to the link given below.

link

B.  When multiplying two rational expressions together, you must first have a common denominator.

Step-by-step explanation:

Option A

When dividing one rational expression by another rational expression, you can rewrite your  expression as a multiplication problem.

Option B

When multiplying two rational expressions together, you must first have a common denominator.

This is not necessary, as according to Option D, the numerators get multiplied together  while the denominators get multiplied together.

Therefore Option B is NOT TRUE.

Option C

When adding two rational expressions together, you must first have a common denominator.

This common denominator is the Lowest Common Multiple of the two denominators. Take for an example: