Calculate the derivative of the function. hint [see example 1.] f(x) = 7x + x2

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

Find the value of x for which the lines are parallel.

Find and simplify an expression for the area of five rows of x squares with side lengths of x centimeters.