Here you go, hope this helps!
(7w^2-7w-8)-(5w^2+2w-3)= 7w^2-7w-8-5w^2-2w+3=7w^2-5w^2-7w-2w-8+3=2w^2-9w-5
The answer to your question is similar
Your answer is A :D Hope It Works !
B, because the height of the boys can be anywhere between any positive number, however not negative because you can't be a negative height.
D, its is non-linear because their heights won't be going up by the same amount each time your x-value increases because the human body grows at different rates, it will be increasing because the human body is always growing until death.
