The essentials of descriptive geometry . geometry it has been thought well to include them here for theconvenience of the student. It is to be understood that no attempt has been made to proveany of the constructions, and also that the particular construc-tion given may not be the onlymethod of arriving at the sameresult. The attempt has been made todraw the figure in such a waythat the construction will bemore or less obvious, and there-fore the explanation has beenmade as brief as possible. Themethods here given have beenfound by experience to be themost practical constructions forthis kind
The essentials of descriptive geometry . geometry it has been thought well to include them here for theconvenience of the student. It is to be understood that no attempt has been made to proveany of the constructions, and also that the particular construc-tion given may not be the onlymethod of arriving at the sameresult. The attempt has been made todraw the figure in such a waythat the construction will bemore or less obvious, and there-fore the explanation has beenmade as brief as possible. Themethods here given have beenfound by experience to be themost practical constructions forthis kind of work. Given the length of one side to construct a regular pentagon. Let AB be the given side. With AB as a radius and B as acenter draw the arc NPAQC. With A as a center and AB as theradius draw the arc MPBQE. With P as a center and the sameradius draw the arc MAOBN. Draw the lines PQ, MC, NE,thus locating E and C. With E and C as centers and AB asradius draw arcs intersecting at D. ABDCE, then, is the re-quired regular pentagon. 197. igS ESSENTIALS OF DESCRIPTIVE GEOMETRY Given the length of one side to construct a regular hexagon. Let AB be the given side. With A and B as centers and ABas radii draw arcs intersecting at O. This will be the center ofthe hexagon. With O as a center and a radius equal to OA drawthe circumscribing circle. Lay off chords on this circle equal inlength to AB, thus locating points C, D, E, and F. ABCDEFis the required hexagon. ^ ^ E ^ P D e; ^ ^
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Keywords: ., bookcentury1900, bookdecade1910, bookidcu3192400462, bookyear1915
