since the the path surounds both sides of the garden you have to add 2 x instead of just x
let me show you what i mean. 10=garden width and 3=path width=x
since it is a square, we can calculate the area by taking one side and squaring it so you get (10+2x)^2 which is 16^2 since x is 3, the width of the garden
to do simaler problems just use thei formula (garden length+2path length)^2 or (garden length+2path length)times(garden length+2path length)
