The domain of given function is <u>All real numbers</u>
For each value of x the function is defined.
Example -
The value is 
The value is 4
The answer is C
Explaining:
Answer:
D
Step-by-step explanation:
We can test each pair making each ratio into its simplest form.
For A 2/3 is already in its simplest form and 9/15=3/5. they are not equivalent.
For B, 5/8 is already in its simplest form and 15/21=5/7. they are not equivalent.
For C, 3/12=1/4, and 6/18=1/3. They are not equivalent.
For D, 4/10=2/5, and 12/30=2/5. They are equivalent.
Answer is C. 7/12 has the reciprocal of 12/7. When You multiply by a reciprocal, you just switch the numerator and denominator. The answer does NOT become negative. It would change the fraction itself.
Example:
3/6= 6/3
5/7= 7/5
