Answer:
a.) x²+h²+2xh-8x-8h
b.) h+2x-8
Step-by-step explanation:
A.) you just plug in x+h wherever there's an x
which means you have
(x+h)²-8(x+h)
simplify and get
x²+h²+2xh-8x-8h
we already know what f(x+h) is so we just need to subtract f(x) we have
x²+h²+2xh-8x-8h-x²+8x
simplify and get
h²+2xh-8h
Divide this by h and get
h+2x-8
Answer:

Step-by-step explanation:
Let's expand the expression bit by bit.
by FOIL.
We have that
.
So, the answer is 
Answer:
28 square metres
Step-by-step explanation:
Calculate the total surface area of the glass covered part of the rectangular aquarium
Surface area = 2(4 × 2) + 2(3 × 2)
= 16 + 12
Protective film needed = 28 square metres
The answer is
4 hope it helps