 | Adrien Marie Legendre - Geometry - 1819 - 574 pages
...' . : .'•!. ..',•. - : V. -. '-.I Of planes and solid angles. .... . . 313. A 8TRAIGHT line is perpendicular to a plane, when it is perpendicular to every straight line in the plane which passes through the foot of the perpendicular (326). Reciprocally, the plane, in... | |
 | Pierre Simon marquis de Laplace, Thomas Young - Capillarity - 1821 - 402 pages
...being unity, 1°=:.01 7453293, 1'=.000290888, and 1"=: .000004848. 145. DEFINITION. A straight line is perpendicular to a plane, when it is perpendicular to every straight line meeting it in that plane. 146. DEFINITION. A plane is perpendicular to a plane, when all the straight... | |
 | Adrien Marie Legendre, John Farrar - Geometry - 1825 - 280 pages
...perimeter. PART SECOND. SECTION FIRST. Of Planes and Solid Angles, DEFINITIONS. 313. A STRAIGHT line is perpendicular to a plane, when it is perpendicular to every straight line in the plane which passes through the foot of the perpendicular (326). Reciprocally, the plane, in... | |
 | Adrien Marie Legendre, John Farrar - Geometry - 1825 - 294 pages
...perimeter. PART SECOND. SECTION FIRST. Of Planes and Solid Jingles. DEFINITIONS. 313. A STRAIGHT line is perpendicular to a plane, when it is perpendicular to every straight line in the plane which passes through the foot of the perpendicular (326). Reciprocally, the plane, in... | |
 | Timothy Walker - Geometry - 1829 - 138 pages
...angles, it is evident that they have the properties of linear angles (20, 21, 22, 34, 35, 39). 127. — A line is said to be perpendicular to a plane when it is perpendicular to all the straight lines which can be drawn through its foot in the plane — . For then it will make... | |
 | John Playfair - Geometry - 1829 - 210 pages
...GEOMETRY. BOOK XI. OF THE INTERSECTION OF PLANES. DEFINITIONS.— See Notes. 1. A straight line is perpendicular to a plane, when it is perpendicular to every straight line meeting it in that plane. 2. A plane is perpendicular to a plane, when all the straight lines drawn... | |
 | John Radford Young - Astronomy - 1833 - 308 pages
...not in the same straight line, the two planes passing through them must coincide and form but one. A straight line is said to be perpendicular to a plane when it is perpendicular to every straight line in that plane, drawn through ilsjbot, or the point where the perpendicular meets the plane. These definitions... | |
 | Charles Davies - Geometry, Analytic - 1836 - 370 pages
...co-ordinates of every point of the plane. PROPOSITION VII. PROBLEM. To find the equation of a plane. A line is said to be perpendicular to a plane when it is perpendicular to every line passing through its foot and lying in the plane : and conversely the plane is said to be perpendicular... | |
 | Euclid, James Thomson - Geometry - 1837 - 410 pages
...being common, ADB is equal (I. 32.) to BHC, and is therefore a right angle. BOOK XI. DEFINITIONS. 1. A STRAIGHT line is said to be perpendicular to a plane when it makes right angles with all straight lines meeting it in that plane. 2. The inclination of two planes... | |
 | Benjamin Peirce - Geometry - 1837 - 216 pages
...perpendicular to each other. 316. Definitions. A straight line is perpendicular Line Perpendicular to a Plane. to a plane, when it is perpendicular to every straight line drawn through its foot in the plane. Reciprocally, the plane, in this case, is perpendicular to the line.... | |
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A straight line is perpendicular to a plane when it is perpendicular to every straight line drawn in the plane through its foot; that is, through the point in which it meets the plane. 
