Hart, C. A. (Clara Avis), b. 1863, Feldman, Daniel D., b. 1872 · New York, American Book Co · leaf 225
here are ?- of these unit squares in a row on AD, and s rows of thesesquares in rectangle ABCD. 5. .-. the area of ABCD = r • 5. 6. But r and s are the measure-numbers oi AD and AB, respectively, referredto the linear unit u. 7. .-. the area of ABCD = ADAB. q.e.d. Reasons 1. § 335. 2. § 63. 3. §…
Geometry, Plane · Geometry, Solid
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