 | George Roberts Perkins - Geometry - 1856 - 460 pages
...the two planes is in a straight line. THEOREM Iv. If a straight line is perpendicular to each of two straight lines at their point of intersection^ it is perpendicular to the plane of these lines. Let AP be perpendicular to the two lines PB, PC, at their point of intersection P ; then... | |
 | George Roberts Perkins - Geometry - 1860 - 472 pages
...the two planes is in a straight line. THEOREM IV. If a straight line is perpendicular to each of two straight lines at their point of intersection, it is perpendicular to the plane of these lines. Let AP be perpendicular to the two* lines PB, PC, at their point of intersection P ; then... | |
 | Benjamin Greenleaf - Geometry - 1862 - 518 pages
...straight line. PROPOSITION IV. — THEOREM. 401. If a straight line is perpendicular to each of two straight lines, at their point of intersection, it is perpendicular to the plane in which the two lines lie. Let the straight line AB be perpendicular to each of the straight lines... | |
 | Benjamin Greenleaf - Geometry - 1861 - 638 pages
...straight line. PROPOSITION IY. — THEOREM. 401. If a straight line is perpendicular to each of two straight lines, at their point of intersection, it is perpendicular to the plane in which the two lines lie. Let the straight line AB be perpendicular to each of the straight lines... | |
 | Adrien Marie Legendre - Geometry - 1863 - 464 pages
...line ; which was to be proved. PROPOSITION IY. THEOREM. If a straight line is perpendicular to two straight lines at their point of intersection, it is perpendicular to the plane of those lines. AP be perpendicular to every line of the plane which pusses through P, and consequently, to the plane... | |
 | Benjamin Greenleaf - Geometry - 1863 - 504 pages
...straight line. B 1> PROPOSITION IV. — THEOREM. 401. If a straight line is pcrpemlicular to each of two straight lines, at their point of intersection, it is perpendicular to the plane in which the two lines lie. Let the straight line AB be perpendicular to each of the straight lines... | |
 | Benjamin Greenleaf - Geometry - 1868 - 340 pages
...straight line. PROPOSITION IV. — THEOREM. 401. If a straight line is perpendicular to each of two straight lines, at their point of intersection, it is perpendicular to the plane in which the two lines lie. Let the straight line AB be perpendicular to each of the straight lines... | |
 | William Chauvenet - Geometry - 1871 - 380 pages
...PROPOSITION V.— THEOREM. / / • • '"( ' ' 13. If a straight line is perpendicular to each of two straight lines at their point of. intersection, it is perpendicular to the plane of those lines. Let AP be perpendicular to PB and PC, at their intersection P; then, AP is perpendicular to the plane... | |
 | William Chauvenet - Mathematics - 1872 - 382 pages
...required perpendicular. PROPOSITION V.— THEOREM. 13. If a straight line is perpendicular to each of two straight lines at their point of intersection, it is perpendicular to the plane of those lines. Let AP be perpendicular to PB and PC, at their intersection P; then, AP is perpen- j^ dicular to the... | |
 | Charles Davies - Geometry - 1872 - 464 pages
...; which, was to be proved. • PROPOSITION IV. THEOREM. If a straight line is perpendicular to two straight lines at their point of intersection, it is perpendicular to the plane of those lines. AP be perpendicular to every straight line of the plane which passes through P, and consequently, to... | |
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If a straight line is perpendicular to each of two other straight lines at their point of intersection, it is perpendicular to the plane of the two lines. 
