Solutions: Let us consider.

The width of the nursery is \[x\]  and length is \[y\] .

Presently, as per the inquiry, we can communicate the given condition as;

\[y-x\text{ }=\text{ }4\]

also,

\[y\text{ }+\text{ }x\text{ }=\text{ }36\]  

Presently, taking \[y-x\text{ }=\text{ }4\text{ }or\text{ }y\text{ }=\text{ }x\text{ }+\text{ }4\]  

For \[y\text{ }+\text{ }x\text{ }=\text{ }36,\text{ }y\text{ }=\text{ }36-x\]

The graphical portrayal of both the condition is as per the following:

From the chart you can see, the lines crosses each other at a point\[\left( 16,\text{ }20 \right)\] . Henceforth, the width of the nursery is 16 and length is 20.