Is the relationship for Camille’s puppies weight in terms of linear or nonlinear

If 1 is divided by the sum of y& 4.the result is equal to 3 divided by 4, find the value of m

How do i simply this expression (quadratic formula basis) on a ti-84 or normal calculator?

What is the greatest number of parts of a circle that can be formed by cutting the circle with 7 straight cuts? (note: the parts do not have to be equal in size)