Lessons on form, for teachers [of geometry].

A B C acute angles already angles fig base Bisect bounded called centre CHAPTER chord circle circumference consequently contained corresponding described diagonals diameter divided draw drawn edges eight equal equal and similar equilateral triangle equivalent expression faces figure five formed four four acute Geometry given half Hence hexagon inscribed interior isosceles triangle joined latter length less LONDON magnitude manner measured meeting obtain obtuse angles octagon parallel parallelogram pentagon perimeter perpendicular plane angles point of intersection points and forming polygon position prism produced prove pupils pyramid quadrilateral radius rectangle regular polygon respectively rhombus right angles right-angled triangle sector sides solid angles square TEACHER termed third three acute angles three angles Three obtuse Three straight lines triangle ABC vertex vertices yard