The area of a triangle is derived as follows;
[tex]\begin{gathered} A=\frac{1}{2}\times b\times h \\ \text{Area}=12.75,\text{base}=3,\text{ therefore height would be} \\ 12.75=\frac{1}{2}\times3\times h \\ 12.75=\frac{1\times3\times h}{2} \\ \text{Cross multiply and you'll have} \\ \frac{12.75\times2}{3}=h \\ 8.5=h \end{gathered}[/tex]The height o the triangle is 8.5 meters