Books Books A STRAIGHT line is perpendicular to a plane, when it is perpendicular to every straight line which it meets in that plane. A Course of Mathematics: In Two Volumes. For the Use of Academies, as Well ... - Page 306
by Charles Hutton - 1818 ## Solid Geometry

George C. Shutts - 1913 - 212 pages
...LINE. The point in which a line meets a plane is the foot of the line. 446. PERPENDICULAR TO A PLANE. A line is perpendicular to a plane when it is perpendicular to every line in the plane passing through its foot. The plane is then said to be perpendicular to the line. PROPOSITION... ## Solid Geometry

Walter Burton Ford, Charles Ammerman - Geometry, Solid - 1913 - 184 pages
...The point where a line intersects a plane is called the foot of the line on that plane. A straight line is perpendicular to a plane when it is perpendicular to every straight line in the plane drawn through its FIG. 170 (a) FIG. 170 (6) foot. The plane is then also... ## Practical Geometry and Graphics for Advanced Students

Joseph Harrison, George Albert Baxandall - Geometry, Descriptive - 1913 - 714 pages
...parallel to a plane when the two do not meet each other, though produced. Definition 4. A straight line is perpendicular to a plane, when it is perpendicular to every straight line which meets it in that plane. Definition 5. Two planes are perpendicular to each other... ## Plane and Solid Geometry

Walter Burton Ford, Charles Ammerman - Geometry, Plane - 1913 - 378 pages
...The point where a line intersects a plane is called the foot of the line on that plane. A straight line is perpendicular to a plane when it is perpendicular to every straight line in the plane drawn through its Fio. 170 (a) Fio.170 (b) foot. The plane is then also... ## Solid Geometry

William Betz, Harrison Emmett Webb - Geometry, Solid - 1916 - 214 pages
...Z FCE. AA CE = A FCE (why ?) and AE=FE. AABE - = AFBE (why?) and Z.ABE=Z.FBE. .'. AB^BE. Why? 547. A line is perpendicular to a plane when it is perpendicular to all lines in the plane drawn through its foot. In that case, also, the plane is said to be perpendicular... ## Plane and Solid Geometry

William Betz - Geometry - 1916 - 536 pages
...Z.ACE =/.FCE. A ACE = AFCE (why?) and AE=FE. A ABE =AFBE (why?) and ^ABE=Z.FBE. .-. AB.LBE. -Why? 547. A line is perpendicular to a plane when it is perpendicular to all lines in the plane drawn through its foot. In that case, also, the plane is said to be perpendicular... ## Solid Geometry

Charles Austin Hobbs - Geometry, Solid - 1921 - 216 pages
...lines are perpendicular or oblique to each other. RELATIONS OF LINES AND PLANES A line is said to be perpendicular to a plane when it is perpendicular to every line in the plane drawn through its foot; at the same time the plane is said to be perpendicular to the line.... 