You are building a right-angled triangular flower garden along a stream as shown in the figure.

The fencing of the left border costs $8 per foot, while the fencing of the lower border costs $2 per foot. (No fencing is required along the river.) You want to spend $320 and enclose as much area as possible. What are the dimensions of your garden, and what area does it enclose? [The area of a right-triangle is given by
A = xy/2.]
left border ft=

bottom border ft=

garden area ft^2