A Rectangular Area of 3200 Ft $2$ Is to Be Fenced Off

Essay

A rectangular area of 3200 ft $2$ is to be fenced off. Two opposite sides will use fencing costing $1 per foot and the remaining sides will use fencing costing $2 per foot. Find the dimensions of the rectangle of least cost. Compute the value of $\lambda$ . What does $\lambda$ represent?