| Richard Pears Wright - 1882 - 136 pages
...angles thus formed are equal to one another, each of these angles is a right angle. When two straight **lines form a right angle they are said to be perpendicular to** one another. Let us suppose the sides of a right angle to be movable, like the legs of a pair of compasses.... | |
| George Anthony Hill - Geometry - 1888 - 202 pages
...one-half right angles to his right? Lesson 19. 1. Define perpendicular lines and oblique lines. If **two lines form a right angle, they are said to be perpendicular to each other** ; if they form any other angle, they are said to be oblique to each other. Abbreviation : The sign... | |
| George Anthony Hill - Geometry - 1888 - 200 pages
...one-half right angles to his right? Lessen 19. 1. Define perpendicular lines and oblique lines. If **two lines form a right angle, they are said to be perpendicular to each other** ; if they form any other angle, they are said to be oblique to each other. Abbreviation: The sign _L... | |
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