If a ball is thrown into the air with a velocity of 45 ft/s, its height (in feet) after t seconds is given by y = 45t - 16t2. Find the velocity when t = 2.

Afarmer has a large field that is x feet in length. he wants to fence in a rectangular section in the middle of the field , leaving a length of 100 feet of open field behind each end of the fenced rectangle.he also wants the width of the fenced-in space to be 100 feet less than its length. find the expressions to represent the length and width of the fenced section of the field