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CHAPTER VIIMBABURRNENT OF ARRAS.
887
root (of the quotient resulting thus), the value of the diameter happens to result. In relation to a regular circular figure, the measure of the area and the circumference are to be made out as explained before.
An example in illustration thereof. 164. In the case of a regular circular figure, the accurate measure of the area has been pointed out to be 5. Caloulate quickly and tell me what the diameter of this circlo) may bo.
On knowing the approximate measure as well as the accurate measure of an area, the rule for arriving at a quadrilateral figure with two equal sides as well as at a quadrilateral figuro with throo equal sider, baving those samo approximate and accurate mcasures (as such measures of their aroas) :
165). In the case of the quadrilateral with) two equal siden, the square root of the difference between the squares of the (approximate and accurate) mensures of the aron is to ho ohtainod. On adding this square root) to the optionally chosen quantity and on subtraoting (the samo square root from the same optionally obosen quantity), the base and the top-sido are so obtained as to have to be divided by the square root of the optional quantity, The approximato measure of the area gives rise to the valuo of the sides so as to bave to be divided by the square root of the optional quantity.
165. If R represents the approximate area of a qurulrilateral with two oqual sides, and the accurate valao thoroof, and p in the optionally choron number, then
NR -
bage =
P
P-NR- !
op-side
and cach of the
WP
equal sides - If a, b, c and d bo tho moasures of the wider of
NP the quadrilateral with two equal sides, then it may be sewn that
