Solution:
To find the area, A, of a triangle, the formula is
[tex]\begin{gathered} A=\frac{1}{2}bh \\ A\text{ is the area } \\ b\text{ is the base} \\ h\text{ is the height} \end{gathered}[/tex]
Given that;
[tex]\begin{gathered} A=84\text{ m}^2 \\ h=12\text{ m} \end{gathered}[/tex]
Substitute the values of the variables into the formula above
[tex]\begin{gathered} A=\frac{1}{2}bh \\ 84=\frac{1}{2}\times b\times12 \\ 84=6b \\ b=\frac{84}{6} \\ b=14\text{ m} \end{gathered}[/tex]
Hence, the measure of the base, b is 14 m
