What pattern do you see in the powers of 3

Apublic library wants to place 4 magazines and 9 books on each display shelf. the expressions 4s +9s represents the total number of items that will be displayed on s shelves. simplify this expression

In which form is the following function written? y = - 2(x – 3)(x + 5)

The perimeter of the rectangle is 120 feet. if the length of the rectangle is ten feet more than the width ,what are the dimensions (length and width) of the rectangle?