The basic purpose of algebra has always been to find the solution of a mathematical problem which involves an unknown quantity. Areas could not be measured and there were only methods for calculation in particular cases.
Most everyday problems involve one unknown quantity and can be reduced to a linear equation.
Problems of area and perimeter involve two unknowns, for example, length and width. Babylonians drew up tables of area and perimeter gaining an advantage over peoples who thought that all plots of land with the same perimeter had the same area. As the perimeter is the distance around the plot it could easily be measured. Very little else is known about him and he is thought to have lived around 400AD and was the first to use symbols to abbreviate his thoughts. At this time it was thought that algebra was used to develop the mind of the rulers rather than solve practical problems.