We will draw the figure
In a new scale, the new scale is
![1\text{ unit= 3 cm}](https://img.qammunity.org/2023/formulas/mathematics/college/84tbr85s2wk51vuo3dpvnjoe0xs8y9bec6.png)
Note that the draw above is a square of side 18cm, therefore in the new scale the side of the square have to be drawn using
![(18cm)/(3cm)=6\text{ }units](https://img.qammunity.org/2023/formulas/mathematics/college/r71c4fgdgxdg7wi9tijygozve2mh27c7v9.png)
That is, if we change the units our new square have a side of 6 units as follows