What is the factored form of z^2– 9?

What is the slope simplify your answer and write it as a proper fraction, improper fraction, or integer

Monica build a remote control toy airplane for science project to test the plane she launched it from the top of a building the plane travel a horizontal distance of 50 feet before landing on the ground a quadratic function which models the height of the plane in feet relative to the ground at a horizontal distance of x feet from the building is shown

Put the equation in slope intercept form by solving for y