 | 1876
...figures having the same area what one has the least perimeter? 5. 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. 6. A triangular pyramid is one-third of a triangular... | |
 | Elias Loomis - 1877 - 443 σελίδες
...common section. Hence, if two planes, etc. PROPOSITION IV. THEOREM. If a straight line be perpendicular to each of two straight lines at their point of intersection, it will be perpendicular to the plane in which these lines are. Let the straight line AB be perpendicular to... | |
 | J. B. Millar - 1878 - 202 σελίδες
...another, their common section is a straight line 2 Theorem III. If a straight line be perpendicular to each of two straight lines at their point of intersection, it shall also be perpendicular to their plane 3 Theorem IV. Every plane which contains the normal to another... | |
 | Isaac Sharpless - 1879 - 266 σελίδες
...the plane BC; it is therefore their common section. Proposition 4. Theorem.—If a straight line be at right angles to each of two straight lines at their point of intersection, it is at right angles to the plane in which these straight lines are. Let AB be at right angles to each... | |
 | Euclides, James Hamblin Smith - 1879 - 349 σελίδες
...0, ED Note. — The Propositions which follow are numbered as in iluolid. PROPOSITION IV. THEOREM. If a straight line stand at right angles to each of two i lines, at the point of their intersection, it must also be at right angles to the plane that passes... | |
 | Oxford univ, local exams - 1880
...figure inscribed in a circle is equal to the sum of the rectangles contained by its opposite sides. 12. If a straight line stand at right angles to each of...straight lines at their point of intersection, it shall also be at right angles to the plane which passes through them, that is, to the plane in which... | |
 | Isaac Todhunter - 1880 - 400 σελίδες
...planes AB and BC cannot but be a straight line. Wherefore, if two planes &c. QED PROPOSITION 4. THEOREM. If a straight line stand at right angles to each of two straight lines at the point of their intersection, it shall also be at right angles to the plane which passes through... | |
 | Woolwich roy. military acad, Walter Ferrier Austin - 1880
...sides, find the area of the polygon, and hence prove that Trr2 is the area of a circle of radius r. 1. If a straight line stand at right angles to each of two straight lines at the point of their intersection, it shall be at right angles to the plane which passes through them.... | |
 | Cornell University - 1880
...triedral angles, a segment of a sphere, the axis of a parabola. 2. If a straight line be perpendicular to each of two straight lines at their point of intersection, it is perpendicular to the plane of those lines. 3. Two prisms are equal, if three faces including a triedral... | |
 | 1883
...shall be similar to one given rectilineal figure, and equal to another giveu rectilineal figure. 16. If a straight line stand at right angles to each of two straight lines at the point of their intersection, it shall also be at right angles to the plane which passes through... | |
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If a straight line stand at right angles to each of two straight lines at the point of their intersection, it shall also be at right angles to the plane which passes through them, that is, to the plane in which they are. 
