The area of a rectangle is equal to the product of its base and altitude. Given R a rectangle with base b and altitude a. To prove R = a X b. Proof. Let U be the unit of surface. .R axb U' Then 1x1 But - is the area of R.
A Treatise on Mensuration, Both in Theory and Practice - Page 91
by Charles Hutton - 1788 - 703 pages
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