Domain. The domain of a function is the complete set of possible values of the independent variable. In plain English, this definition means: The domain is the set of all possible x-values which will make the function "work", and will output real y-values.
You will start the 5 on the Y axis
from there go down 3 and to the right 4 times
<u />a=2
2a=2*2=4 (replace a with 2)
The answer is 4.
I can’t see it the picture