4tQ 



GEOMETRY. 

 PROBLEM XXX. 



To find the Ce?itre of a given Polygon^ or the Centre of its in^ 

 scribed or circumscribed Circle, 



Bisect any two sides with the per- 

 pendiculars mOi no ; and their inter- 

 section will be the centre. Then, 

 with the centre o, and the distance 

 only describe the inscribed circle j or 

 with the distance to one of the an- 

 gles, as A, describe the circumscrib- 

 ing circle. 



Note. This method %yni also circumscribe a circle- 

 about any given oblique triangle. 



PROBLEM XXXI. 

 In any given Triangle to inscribe a Circle* 



Bisect any two of the angles 

 with the lines Ac, Bo, and o will 

 be the centre of the circle. Then, 

 with the centre o, and radius the 

 nearest distance to any one of the 

 «ides, describe the circle. 



PROBLEM XXXII . 



About any given Triangle to circwnscribe a Circle, 



C 



Bisect any two of the sides A 

 B, B C, with the perpendiculars 

 wo, no. With the centre o, and 

 distance to any one of the angles, 

 describe the circle. 



PROBLEM 



