## Elements of Geometry: Containing the First Six Books of Euclid: With a Supplement ... to which are Added, Elements of Plane and Sphericale Trigonometry ... From the Last London Ed., Enl |

### From inside the book

Results 1-5 of 27

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**equilateral**triangle is that which has three equal sides . 20. An isosceles triangle is that which has only two sides equal . ΔΔΔ 21. A scalene triangle is that which has three unequal sides . 22 A right angled triangle is that which ... Page 11

... are equal to one another . வ 11. " Two straight lines which intersect one another , cannot be both pa " ralle to the same straight line . ' PROPOSITION I. PROBLEM . To describe an

... are equal to one another . வ 11. " Two straight lines which intersect one another , cannot be both pa " ralle to the same straight line . ' PROPOSITION I. PROBLEM . To describe an

**equilateral**triangle upon OF GEOMETRY . BOOK I. 11. Page 12

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**equilateral**triangle upon a given finite straight line . Let AB be the given straight line ; it is required to describe an equi . lateral triangle upon it . From the centre A , at the dis- tance AB , describe ( 3. Postulate ) the circle ... Page 15

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**equilateral**triangle is also equiangular PROP . VI . THEOR . If two angles of a triangle be equal to one another , the sides which subtend or are opposite to them , are also equal to one another . Let ABC be a triangle having the angle ... Page 17

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**equilateral**triangle DEF ; then join AF ; the straight line AF bisects the angle BAC . Because AD is equal to AE , and AF is com- mon to the two triangles DAF , EAF ; the two sides DA , AF , are equal to the two sides EA , AF , each to ...### Other editions - View all

### Common terms and phrases

ABC is equal ABCD adjacent angles altitude angle ABC angle ACB angle BAC base BC bisected centre chord circle ABC circumference cosine cylinder demonstrated described diameter divided draw equal and similar equal angles equiangular equilateral equilateral polygon equimultiples Euclid exterior angle fore four right angles given rectilineal given straight line greater Hence hypotenuse inscribed join less Let ABC Let the straight magnitudes meet multiple opposite angle parallel parallelogram parallelopiped perpendicular polygon prism PROB PROP proportional proposition quadrilateral radius ratio rectangle contained rectilineal figure remaining angle right angled triangle SCHOLIUM segment semicircle shewn side BC sine solid angle solid parallelopiped spherical angle spherical triangle square straight line BC THEOR touches the circle triangle ABC triangle DEF wherefore