1. In a right triangle, C being the right angle, 2. In a right triangle, 7 and m being the projections of a and b on c, and h, the altitude on c, h2=1Xm. a2=1Xc, b2=mxc. 3. In an oblique triangle, m being the projection of b on c, Art. 342. Art. 349. Art. 393. Art. 353. Art. 363. 7. If land m are the segments of c made by the bisector of the angle opposite, a: b=l: m. Arts. 332, 336. 8. If I and m are the segments of a line, a, divided in extreme and mean ratio, and 1 > m, a : 1=l: m. Art. 370. 10. In circles, C: C'=R: R'; also C: C' =D : D'. Art. 442. 2. In a triangle, K=√s (s—a) (s—b) (s—c). Art. 393. a2√3 Ex. 4, p. 257. Art. 385. Art. 394. Art. 446. 9. In a segment of a circle, K-sector ▲ formed by the chord and radii of the segment. 10. In a circular ring, K=π (R2 — R12). 11. In any two similar plane figures, K: K'a2: a/2; also a : a=K: VK. 12. In two circles, K: K'= R2 : R'2 = D2 : D'2=C2 : C'2; also R ; R' =D: D' = C ; C' = √ K : √K'. Art. 449. Art. 399. Art. 314. Art. 452. Art. 314. Similar tables are used for the unit of weight, the gram; for the unit of capacity, the liter; for the unit of land measure, the are; and for the unit of wood measure, the stere. TABLE FOR SQUARE MEASURE 100 sq. mm. =1 sq. cm. 100 sq. cm. =1 sq. dm., etc. TABLE FOR CUBIC MEASURE 1000 cu. mm. =1 cu. cm. 1000 cu. cm. 1 cu. dm., etc. 1 cu. dm. weight of 1 cu. cm. of water at 39.2° Fahrenheit |