## Marks' First Lessons in Geometry: In Two Parts : Objectively Presented and Designed for the Use of Primary Classes in Grammar Schools, Academies, Etc |

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Marks' First Lessons in Geometry: Objectively Presented, and Designed for ... Bernhard Marks No preview available - 2008 |

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acute angle adjacent angles Blue adjacent angles Green adjacent angles Yellow angle b c d angle ƒ angles are equal angles whose vertices AXIOM called circle circumference curved line DEMONSTRATION DEVELOPMENT LESSON Diagram draw equal sides equilateral triangle exterior and interior Fasquelle's fn d Geometry given to Fig greater half the arc inches long included angle interior alternate angles interior angles Red interior opposite angles isosceles triangle line c d means of Fig measured by half obtuse angle opposite exterior pairs of adjacent parallel parallelogram particular name perpendicular polygon producing the line PROPOSITION Prove the interior quadrilateral radii radius Read four rectangle rhomb rhomboid right angles right-angled triangle scalene triangle SCHOOL secant separately equal side A B square inches straight lines a b tangent TEST LESSON THEOREM thing three angles three names trapezium trapezoid triangle a b c units long vertex wish to prove Woodbury's

### Popular passages

Page 74 - PERIPHERY of a circle is its entire bounding line ; or it is a curved line, all points of which are equally distant from a point within called the center.

Page 24 - An ACUTE ANGLE is one which is less than a right angle ; as the angle DEF.

Page 147 - If two triangles have the three sides of the one equal to the three sides of the other, each to each, the triangles are congruent.

Page 88 - Things which are double of the same thing, are equal to each other. 7. Things which are halves of the same thing, are equal to each other. 8. The whole is greater than any of its parts. 9. The whole is equal to the sum of all its parts. 10. All right angles are equal to each other. II. From one point to another, only one straight line can be drawn.

Page 25 - Then it is called an acute angle. An acute angle is one which is less than a right angle.

Page 83 - A segment bounded by a diameter and a semicircumference is a "semicircle." A semicircle is half a circle. Read four segments each larger than a semicircle. The part of the circle between the two radii of, oi, and the arc/z, is called a

Page 152 - PROPOSITION XXII. THEOREM. DEMONSTRATION. We wish to prove that The angle formed by a tangent and a chord meeting at the point of contact is measured by half the intercepted arc. Let the tangent CAB and the chord AD meet at the point of contact A ; then will the angle BAD be measured by half the intercepted arc A D. For draw the diameter AE F. Because AB is a tangent, and AE a radius at the point of contact, the angle BAF is a right angle, and is measured by the semicircle AD F.