A Geometry for Beginners |
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ABCD Fig adjacent angles altitude angles are equal Axiom axis base bisectors bisects body breadth called centre chord circumference circumscribed concave angle cone Construct a triangle corner Corollary cube curved cylinder decagon diagonal diameter distance divide draw a line edge ellipse equilateral triangle equivalent example Exercises Exercises.-1 exterior angle figure find the area Find the side four frustum Geometry given angle given circle given line given point Hence homologous sides horizontal hypotenuse inscribed angle inscribed regular intersection isosceles triangle join legs less radius line drawn magnitudes number of sides opposite parallel lines parallelogram parallelopiped perimeter perpendicular prism Problem Proof proportional pyramid quadrilateral radii ratio rectangle regular hexagon regular polygon rhombus right angle right triangle ruler scale sector segment shape similar triangles solid angle sphere square meters straight line tangent Theorem trapezoid triangle ABC units of length vertex vertical volume
Popular passages
Page 117 - Two triangles are congruent if two sides and the included angle of one are equal respectively to two sides and the included angle of the other.
Page 140 - The area of a rectangle is equal to the product of its base and altitude. Given R a rectangle with base b and altitude a. To prove R = a X b. Proof. Let U be the unit of surface. .R axb U' Then 1x1 But - is the area of R.
Page 141 - The area of a parallelogram is equal to the product of its base and its height: A = bx h.
Page 92 - Hence the arc drawn from the vertex of an isosceles spherical triangle, to the middle of the base, is perpendicular to the base, and bisects the vertical angle.
Page 269 - The altitude of a pyramid is the length of the perpendicular from the vertex of the pyramid to the plane of the base.
Page 124 - A regular polygon of three sides is called an equilateral triangle ; oifour sides, a square ; of five sides, a pentagon ; of six sides, a hexagon ; of seven sides, a heptagon ; of eight sides, an octagon ; of nine sides, a nonagon ; of ten sides, a decagon ; of twelve sides, a dodecagon.
Page 125 - Theorem. — The sum of all the angles of a polygon is equal to twice as many right angles as the polygon has sides, less two.
Page 180 - If in a right triangle a perpendicular is drawn from the vertex of the right angle to the hypotenuse : I.
Page 79 - If two angles of one triangle are equal respectively to two angles of another triangle, the third angles are equal.