What is the simplified expression to (x-5) + (x+1)

Given the graph below state whether or not the relation is a function, and give the domain and range.

How do i do this? i don’t understand

Alina fully simplifies this polynomial and then writes it in standard form. xy2 – 2x2y + 3y3 – 6x2y + 4xy2 if alina wrote the last term as 3y3, which must be the first term of her polynomial in standard form? xy2 5xy2 –8x2y –2x2y