How can I form the equation in this word problem?

Question

A rectangular garden measures 20m by 80m ,A large path of uniform width is to be added to along both shorter sides and one longer side of the garden.The landscape artist doing the work Want to double the garden's area with addition of this path. How wide should the path be?

Answer 1

Does the picture help?

New dimensions $80+2w$ and $20 + w$ so new area is $(80+2w)(20+w)$. And New Area is twice the old area. $\\\\$

The old area was $20\times 80$ so the the new area is $(80+2w)(20+w) = 2(20 \times 80)$.