Answer:
The only untrue statement is
- When multiplying two rational expressions together, you must first have a
common denominator.
Explanation:
A rational expression has a rational numerator and a rational denominator.
To investigate each of these statement, we take two arbitrary rational expressions
Rational expression 1 = (a/b)
Rational expression 2 = (c/d)
Taking the statements one at a time
- When dividing one rational expression by another rational expression, you
can rewrite your expression as a multiplication problem.
(a/b) ÷ (c/d) = (a/b) × (d/c)
This statement is obviously true.
- When multiplying two rational expressions together, you must first have a
common denominator.
(a/b) × (c/d) = (ac/bd)
We do not need b = d to do this multiplication, hence, this statement is false.
- When adding two rational expressions together, you must first have a
common denominator,
(a/b) + (c/d)
We first take an LCM, so that we then have
(ad/bd) + (bc/bd)
= (ad + bc)/bd
This statement is true also.
- When multiplying two rational expressions together, the numerators get
multiplied together while the denominators get multiplied together.
(a/b) × (c/d) = (ac/bd)
This statement is true.
So, only the second statement is not true.
Hope this Helps!!!