| George Roberts Perkins - Geometry - 1856 - 460 pages
...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 - 468 pages
...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 - 520 pages
...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 - 628 pages
...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
...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,... | |
| Benjamin Greenleaf - Geometry - 1863 - 504 pages
...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 - 338 pages
...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
...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... | |
| Charles Davies - Geometry - 1872 - 464 pages
...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,... | |
| William Chauvenet - Geometry - 1872 - 382 pages
...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^... | |
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