The x-intercepts of a parabola are also known as roots.
These are the point(s) at which the graph crosses the x-
axis.
Sketch the points on the graph.
Given the quadratic function for the graph on the
left,
f(x) = (x + 7)(x-3)
determine the roots/x-intercepts of the parabola:

The john deere company has found that revenue,in dollars, from sales of heavy-duty tractors is a function of the unit price p, in dollars, that it charges. if therevenue r is r(p)= -1/2p^2 +1900pa)how much revenue will the company generate if they sell 700 tractors? b) how many tractors does the company want to sell to maximize the revenue?