To find the surface area of a cuboid, add the areas of all 6 faces. We can also label the length (l), width (w), and height (h) of the prism and use the formula, SA=2lw+2lh+2hw, to find the surface area.
Answer of what is the length is 12. if we add all the sides it has to come as 36,so if length=x then width=2x therefore X+X+2X+2X=36 therefore x=6 then width=2x =12.
