Zack is preparing for a marathon and currently weighs 162 pounds. his total body weight can be expressed as 3x^3 + 9x^2, and his body fat weight can be expressed as 3/2x^2. write a function which represent zack's body fat percentage.

Jack has a rectangular piece of land, the area of which is represented by a1 = 9.5l. his brother has a different rectangular piece of land, the area of which is represented by a2 = l(14 − l). let a represent the area in square meters and l represent the length in meters of the pieces of land. the two equations plotted on a graph meet at a point as shown in the image