Answer and explanation:
A rectangle's width is longer than the length
And so given a rectangular lawn 4m by 10m,
the width of the lawn= 10m
the length of the lawn= 4m
If a garden of uniform width is added, then garden's width = 10m
The garden of uniform width is added to the width side of the rectangular lawn( since along the combined side length of the lawn and garden, another garden is added)
The garden added to the combined side length of the lawn and garden has width twice that of the garden = 2*10= 20m
Given that total area of the lawn and two gardens = 72m²
Total area of lawn and 2 gardens(Area of rectangle(lawn+2 garden's)) is length * width
= 4*10+ 10*x+ 20*y=72
Therefore equation for total area of lawn and both gardens is 40+10x+20y=72
Where x is length of second garden attached to the width side of the lawn and y is length of the garden attached to the combined length side of the lawn and first garden
x can be solved
40+10x+20y=72
10x+20y=72-40
10x+20y=32
10x=32-20y
x=32-20y/10
Y can be solved
40+10x+20y=72
10x+20y=72-40
10x+20y=32
20y=32-10x
y=32-10x/20