> ANM y IK '-I OMMTRY 



they are severally equidistant from tin- origin, Ill-cause ..r 

 greater gyinmrm ivrian-jular runnlinatrs ha\r many 



ires over an M.lujue system. 



/// '"wing pages rdinates /</// ///. 



be understood unless the contr rpressly stated. 



EXERCISES 



1 Plot accurately tl..- point,; M.7). (-1. -:,). (o, :,), and (-3,0). 



2. Plot accurately, as vertices of a triangK the point- : 

 and (~4, ~4). Find by measurement the lengths of the sides. and 1 1n- 

 coordinate* of the middle point of each side. 



3 Construct the two lines passing through the points (2, ~7 

 7). and (2. 7) and (~2, ~7), respectively. What is tln-ir point .,f 

 intersection V Find tin; coordinates of tin- middle point of cncli IIIK-. 



4. If the ordinate of a point is 0, where is the point? if it- :.. 

 is 0? if its abscissa is equal to its ordinate? if its abscissa and ordinal' 

 are numerically equal but of opposite signs? 



5 1 .\; :-'S.s each of the conditions of Ex. 4 by means of an equation. 



6. The base of an equilateral triangle, whose side is 5 inches, coincides 

 \\itiith.-j--axis; its middle point is at the origin; what are the coordinates 

 of the vertices? If the axes are chosen so as to coincide with two sides of 

 this triangle, respectively, what are the coordinates of tin- vertices? 



7. A square whose side is 5 inches has its diagonals kin- upon the 

 coordinate axes ; find the coordinates of it> \. -rtices. If a diagonal and 

 an adjacent side are chosen as axes, what are the coordinates of the 

 vertices? of the middle points of the sides? of the center? 



8. Find, by similar triangles, the. coordinates of the point \\liicli 

 bisects the line joining the points ( J. 7) and (I, 1 .. 



9. Show that thj distance fnm the origin to tin- point (n. />) is 

 Vo f + 6*. How far from the origin is the p<unt (./. /,) 



( ". >>' (cf. Art 22.) 



10. Prove, by similar triangles, that the points: (_>. ;;). (1. :)), and 

 '.') lie on the same straight line. 



11. Solve exercises 1 to 4 and lo if the eobrdinate axes mak<- an 

 o(60. AUoif thU:ni-l.. b- i:i . 



Thee minus signs arc written high merely U) indicate that they are 

 ns of quality and not of operation. 



