what is the vale of the function at x=2

The function ƒ is defined by ƒ(x) = (x + 3)(x + 1). the graph of ƒ in the xy-plane is a parabola. which interval contains the x-coordinate of the vertex of the graph of ƒ?

Triangle xyz has vertices x(1,3), y(0,0)

You got a job selling magazines door-to-door. you are paid $100 per day plus $1.50 for each magazine you sell. which recursive formula models this situation?