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CHAPTER VII-XBASUREMENT OP ARKAS.
197
An example in illustration thereof. 48. In relation to a quadrilateral figure, each of whose sidos is 15 (in measure), tell me the practically approximato value of the inscribed and the escribed ciroles.
Thus ends the calculation of practically approximato value in relation to areas.
The Minutely Accurate Calculation of the
Measure of Areas.
Hereafter in the caloulation rogarding the mowurement of areas we shall expound the subject of treatment known as minutely acourato caloulation. And that is as follows:
The rule for arriving at the measure of the perpondicular (from the vertex to the base of a given trianglo) and (also) of tho sogmonts into which the base is thoroby divided):
49. The process of sankramana carried out between the baro and the difference between the squares of the sides as divided by the base gives rise to the values of the two segments of the base) of the triangle. Learned teachers say that the square root of the difference between the squares of (oither of these (segments) and of the (corresponding adjacent) eide gives rise to tbo mousure of the perpendicular.
40. Algebraically represonted--
5= (+4*50*)**:
Va' - or Vbi - C. Here a, b, c, represent the meannres of the sides of trianglo, G, C, the measures of the segments o! the browbone total length iso, and y represents the length of the perpendioular.