Is this a function?explain your choice. be specific by describing the domain and range values that may be problematic

No, this is not a function because this would not pass the vertical line test in which only one y point can be on one x axis not two. As you can see, on (0,3) and (0,(-2)) are on the same x axis. So, not a function.

5x + 5

step-by-step explanation:

you should always add the diagrams and graphs we cannot see. this particular question is kind of borderline because we can make a graph for you.

(f + g)x = -x^2 +3x + 5 + x^2 + 2x

(f + g)x = 5x + 5

the graph of z = 5x + 5 is shown below. always use desmos when in doubt.