Answer :
- Let breadth be x
- Length=4x
We know
[tex]\boxed{\sf Area=Length\times Breadth}[/tex]
[tex]\\ \sf\longmapsto x(4x)=36[/tex]
[tex]\\ \sf\longmapsto 4x^2=36[/tex]
[tex]\\ \sf\longmapsto x^2=\dfrac{36}{4}[/tex]
[tex]\\ \sf\longmapsto x^2=9[/tex]
[tex]\\ \sf\longmapsto x=\sqrt{9}[/tex]
[tex]\\ \sf\longmapsto x=3[/tex]
- Breadth=3m
- Length=4(3)=12m