Which of the following equations represents a line parallel to the line given by y=5x +9?

y = 5x + 1

Step-by-step explanation:

Lines that are parallel to each other on a graph would have the same slope but different y-intercepts. When option A's equation is graphed along with the line given in the question, the lines appear to be parallel.  

Option A should be the correct answer.

Let x represent the edge length of the square end. Then the area of the end of the package is x², and the length of the package is 126 -4x. The overall volume is ...
  V = x²×(126 -4x)
  V = -4x³ +126x²

The volume will be a maximum where the derivative of volume with respect to x is zero.
  V' = -12x² +252x
  V' = -12x(x -21)
This will be zero for x = 0 and for x = 21

The maximum volume of the package is
  V = (21 in)²(126 in -4×21 in)
  V = 18,522 in³