Would the answer be 0 ?

Answer:
4
Step-by-step explanation:
For it to be continuous at x=0 we need the left and right limit at x=0 to be equal. We also need those limits to equal what happens at x=0.
A famous limit is:
As x goes to zero, sin(x)/x goes to 1.
So the left limit at x=0 would be 4(1)=4.
The right limit at x=0 would be a-2(0)=a.
So a=4.
So f(0)=4-2(0)=4 also which is what both limits would equal for x=0 if a=4.