## Elements of Geometry |

### From inside the book

Results 1-5 of 26

Page vii

...

...

**perimeter**. The first section of the second part contains the properties of planes and of solid angles . This part is very necessary for the understanding of solids and of figures in which different planes are considered . We have ... Page 2

...

...

**perimeter**of the polygon . Fig . 7 . 14. The polygon of three sides is the most simple of these figures , and is called a triangle ; that of four sides is called a quadrilateral ; that of five sides , a pentagon ; that of six , a hexa ... Page 20

...

...

**perimeter**in more than two points . THEOREM . 84. The opposite sides of a parallelogram are equal , and the oppo- site angles also are equal . Demonstration . Draw the diagonal BD ( fig . 44 ) ; the two triangles ADB , DBC , have the ... Page 64

...

...

**perimeters**of similar polygons are as their homologous sides , and their surfaces are as the squares of these sides ...**perimeter**of the second figure , as one antecedent , is to its consequent ( Iv ) , or as the side AB is to its ... Page 67

...

...

**perimeter**multiplied by half of the radius of the inscribed circle . For the triangles AOB , BOC , AOC ( fig . 87 ) , which have their Fig $ 7 . common vertex in O , have for their common altitude the radius of the inscribed circle ...### Other editions - View all

### Common terms and phrases

ABC fig adjacent angles altitude angle ACB angle BAD base ABCD bisect centre chord circ circular sector circumference circumscribed common cone consequently construction convex surface Corollary cube cylinder Demonstration diagonals diameter draw drawn equal and parallel equiangular equilateral equivalent faces figure four right angles frustum Geom gles greater hence homologous sides hypothenuse inclination inscribed circle isosceles join less let fall line AC manner mean proportional measure the half meet multiplied number of sides oblique lines opposite parallelogram parallelopiped perimeter perpendicular plane MN polyedron prism proposition pyramid S-ABC quadrilateral radii radius ratio rectangle regular polygon right angles right-angled triangle Scholium segment semicircumference side BC similar solid angle sphere spherical polygons spherical triangle square described straight line tangent THEOREM three plane angles triangle ABC triangular prism triangular pyramids vertex vertices whence