## The Elements of Euclid; viz. the first six books, together with the eleventh and twelfth. Also the book of Euclid's Data. By R. Simson. To which is added, A treatise on the construction of the trigonometrical canon [by J. Christison] and A concise account of logarithms [by A. Robertson].1814 |

### From inside the book

Page 9

... angle EDF , the base BC shall be equal to the base EF ; and the

... angle EDF , the base BC shall be equal to the base EF ; and the

**triangle ABC**to the triangle DEF ; and the other angles to which the equal sides B are opposite , shall be CE equal each to each , viz . the**angle ABC**to the angle DEF ... Page 10

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...

**angle ABC**shall be equal to the angle ACB , and the angle CBD to the angle BCE . In BD take any point F , and from AE the greater , cut 3. 1. off AG equal a to AF , the ... ABC be a triangle having the**angle ABC**equal 10 THE ELEMENTS. Page 11

Euclides Robert Simson. Let ABC be a triangle having the

Euclides Robert Simson. Let ABC be a triangle having the

**angle ABC**equal to the angle ACB ; the side AB is also equal to the side AC . D A Book I. For , if AB be not equal to AC , one of them is greater than the other : Let AB be the ... Page 12

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**angle**ACB ; produce AC , AD to E , F ; therefore , because AC is equal to AD in the**triangle**ACD , the**angles**ECD ...**ABC**, DEF be two triangles , having the two sides AB , AC , equal to the two sides DE , DF , each to each , viz ... Page 16

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**angle**CBA be equal to ABD , each of them is a A D C B D E A B с a Def . 10. right a**angle**; but if not , from the ...**ABC**, therefore the**angles**DBA ,**ABC**are equal to the three**angles**DBE , EBA ,**ABC**: but the**angles**CBE , EBD ...### Other editions - View all

### Common terms and phrases

ABC is given AC is equal altitude angle ABC angle BAC base BC bisected BOOK XI centre circle ABCD circumference common logarithm cone cylinder demonstrated described diameter drawn equal angles equiangular equimultiples Euclid excess fore given angle given in magnitude given in position given in species given magnitude given ratio given straight line gnomon greater join less Let ABC logarithm meet multiple opposite parallel parallelogram AC perpendicular point F polygon prism proportionals proposition pyramid Q. E. D. PROP radius rectangle CB rectangle contained rectilineal figure remaining angle right angles segment side BC similar sine solid angle solid parallelopipeds square of AC straight line AB straight line BC tangent THEOR third triangle ABC triplicate ratio vertex wherefore

### Popular passages

Page 3-7 - IF a straight line be divided into any two parts, the square of the whole line is equal to the squares of the two parts, together with twice the rectangle contained by the parts.

Page 16 - Any two sides of a triangle are together greater than the third side.

Page 26 - Therefore all the angles of the figure, together with four right angles, are equal to twice as many right angles as the figure has sides.

Page 16 - If, from the ends of the side of a triangle, there be drawn two straight lines to a point within the triangle, these shall be less than, the other two sides of the triangle, but shall contain a greater angle. Let...

Page 304 - Again ; the mathematical postulate, that " things which are equal to the same are equal to one another," is similar to the form of the syllogism in logic, which unites things agreeing in the middle term.

Page 4 - DL is equal to DG, and DA, DB, parts of them, are equal ; therefore the remainder AL is equal to the remainder (3. Ax.) BG : But it has been shewn that BC is equal to BG ; wherefore AL and BC are each of them equal to BG ; and things that are equal to the same are equal to one another ; therefore the straight line AL is equal to BC.

Page 147 - If two triangles have one angle of the one equal to one angle of the other and the sides about these equal angles proportional, the triangles are similar.

Page 3-16 - To divide a given straight line into two parts, so that the rectangle contained by the whole, and one of the parts, may be equal to the square of the other part.

Page 159 - SIMILAR triangles are to one another in the duplicate ratio of their homologous sides.