This problem will build on the calculation of the first moment of area (mass) discussed for the calculation of the center of gravity. Your ability to make a graphical interpretation of a problem statement for the location of the centre of gravity (mass) of a simple shapes is being assessed.
\begin{itemize}
\item The height corresponding to a side of a triangle is the distance of the third point to the side.
\item The centre of gravity (CG) of a triangle is at located a third of the height away from each corresponding base.
\item Three lines parallel to each side, at a distance of the third of the corresponding height will intersect at the CG.
\end{itemize}
Draw on a clean sheet of paper (or graph paper if you can afford), points of coordinates A(-8,0), B(1,6) and C(4,-6) and then calculate:
1. the length of base $AB = \underline{\qquad} cm$ and the corresponding height $\underline{\qquad} cm$,
2. $AC = \underline{\qquad} cm$.
