Answer:
f(x)=x^2+3
f(x+y)=(x+y)^2+3
this is done by replacing x with (x+y)
f(x+y)=x^2+2xy+y^2+3
therefore : f(x+y)= x^2+y^2+2xy+3
Answer:
The mean number of deliveries for driver A is less then the mean for driver B by 3 MADs.
So we are given the expression:
÷ 
When we divide fractions, we must flip the second term and change the sign to multiplication:

And then we multiply across:

Then we can break apart all of the like variables for simplification:

When we simplify variables through division, we subtract the exponent of the numerator from the exponent of the denominator. So we then have:



So then we multiply all of these simplified parts together:

So now we know that the simplified form of the initial expression is:
.
Answer:
B should have been the winner. Since B received the majority of the votes, he should be the winner, not A, and it doesnt matter how close was the election or how cmany votes A got in reality. If B had more votes for 1st place, then it should be the winner, not A. I am assuming that there were electoral fraud and someone intentionally didnt count valid votes from B.