The sheet-metal worker's guide : a practical handbook for tinsmiths, coppersmiths, zincworkers, etc., comprising numerous geometrical diagrams and working patterns, with descriptive text (1888)
Crane, W. J. E. (W. J. Eden) · London : Lockwood and Son · leaf 49
37 TRIANGLES. triangles, tliree named with reference to the length of their sides, and three with regard to the sizes of their angles. The first three are : — The equilateral triangle, which has its sides equal (a, Fig. 28). The angles are also equal, and each contains 60°. … Fig. 28. The isosceles triangle (b, Fig. 28), which has two sides equal. These sides may be longer or shorter than the third side. The unequal side is always termed the base, in whatever position the triangle maybe represented; the angles at the base are equal to each other. A scalene triangle (c.…
Sheet-metal work
Internet Archive · Getty Research Institute · Public domain (published before 1931). Free to use for anything.
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