Question

A rancher with 420420 meters of fence intends to enclose a rectangular region along a river​ (which serves as a natural boundary requiring no​ fence). find the maximum area that can be enclosed.

Answer 1

Perimeter of Rectangle: 2W + 2L
One L is the river so we have 3 sides
420m/3 = 140m

Area of Rectangle is WL
140×140= 19,600 Sq meters

I'm assuming you may have another mathematical system the teacher wants you to use. Yet, I get Area is 19,600 Sq meters