For what value of x is the rational expression below undefined? x-1/(x-3)(x+1)

Which describes the difference between the graph of f(x)=x^2 and g(x)=-(x^2-2)

At the "no mutants allowed" country farm, every sheep has 4 legs, every chicken has two legs, and all animals have only 1 head. asked to count how many sheep and chicken are in the fields, a farm boy reports back that there are 140 feet and 50 heads. how many sheep and chicken are there? there are sheep and chicken at the farm.

Having a hard time understanding this question (see attachment).