Answer:
13
Step-by-step explanation:
a negative plus a negative makes a positive
Answer:
4=4
Step-by-step explanation:
Find f (3) when f (x) =2x is the same as finding u when x= 3 ,for y=2x
to evaluate a function substitute the input (the given number or expression ) for the functions variable(place holder x). Replace the x with the number or expression