We want to obtain an equation that can be used to determine the length of the unknown side;
The height of the sign is 3.4metres, and the area of the sign is the maximum allowable area 13 square meters.
The equation we can use to find the length L of the sign is;
[tex]\begin{gathered} L=\frac{A}{H} \\ \text{where A is the area and H is the height of the sign.} \end{gathered}[/tex]Putting in the values, we can obtain L;
[tex]L=\frac{13}{3.4}=3.82m[/tex]