...a line drawn through the vertex parallel to the base. -ve* f1 — 44 GEOMETRY. COROLLARY 1. ^M <Ae interior angles of any rectilineal figure, together...twice as many right angles as the figure has sides. Let ABCDE be a rectilineal figure of & sides. It is required to prove that all the interior angles...

...course be arranged so as not to assume the proposition that the interior angles of a convex polygon together with four right angles are equal to twice as many right angles as the figure has sides. Let there be any convex polyhedral angle with V as vertex, and let it be cut by any plane meeting its...

...angles ; and in any convex polygon the sum of the interior angles, together with four right angles, is equal to twice as many right angles as the figure has sides (Euc. I. 32, Cor.) 110 Congruence. CI — If two triangles have two sides and the included angle in...

...somewhat simpler than, Simson's. 1. The sum of the interior angles of a convex rectilineal figure is equal to twice as many right angles as the figure has sides, less four. For let one angular point A be joined to all the other angular points with which it is not...

...angles. = 180' (fig. 2). FIG. 1. FIG. 2. The sum of the interior angles of any rectilineal figure is equal to twice as many right angles as the figure has sides, less 4. Thus, for example, in the irregular pentagon (fig. 3), = 2 x 5 x 90° - 4 x 90° ; FIG. 3....

...whose altitude is 3 inches. SEPTEMBER, 1909 1. The sum of all the interior angles of any polygon is equal to twice as many right angles as the figure has sides, less four right angles. 2. The angle between two chords which intersect within a circle is measured...

...together equal to two right angles, then the two straight lines shall be parallel. 28—1. 6 8. Prove that all the interior angles of any rectilineal figure...twice as many right angles as the figure has sides. 8 9. (a) If a straight line be bisected and produced to any point, the rectangle contained by the whole...

...acute angle, then AD will be greater than half BC. 2. Prove that the interior angles of any rectilinear figure together with four right angles are equal to...twice as many right angles as the figure has sides. Find the number of sides of a regular polygon, each angle of which is equal to the sum of an angle...

...acute angle, then AD will be greater than half BC. 2. Prove that the interior angles of any rectilinear figure together with four right angles are equal to...twice as many right angles as the figure has sides. Find the number of sides of a regular polygon, each angle of which is equal to the sum of an angle...

...Stated precisely, " the sum of all the internal angles of a closed polygon plus four right angles is equal to twice as many right angles as the figure has sides." So that it is easy from the field notes to find the internal angle at each corner of the figure, and...