 | Elias Loomis - Conic sections - 1849 - 252 pages
...altitudes; and equivalent triangles, whose altitudes are equal, have equal bases. PROPOSITION VII. THEOREM. The area of a trapezoid is equal to half the product of its altitude by the sum of its parallel sides. Let ABCD be a trapezoid, DE its altitude, AB and CD... | |
 | Charles Davies - Geometry - 1850 - 218 pages
...And generally, triangles are to each other as the products of their bases and altitudes. THEOREM X. The area of a trapezoid is equal to half the product of its altitude by the sum of its parallel sides. D Of Rectangles. For, produce AB until BE is equal to... | |
 | Charles Davies - Geometry - 1850 - 238 pages
...And generally, triangles are to each other as the products of their bases and altitudes. THEOREM X. The area of a trapezoid is equal to half the product of its altitude multiplied by the sum of its parallel sides. 90 Of Rectangles. For, produce AB until BE... | |
 | Elias Loomis - Conic sections - 1858 - 256 pages
...altitudes; and equivalent triangles, whose altitudes are equal, have equal bases. PROPOSITION VII. THEOREM. The area of a trapezoid is equal to half the product of its altitude by the sum of its parallel sides. Let ABCD be a trapezoid, DE its altitude, AB and CD... | |
 | Charles Davies - Arithmetic - 1861 - 496 pages
...of its opposite sides, / ! AB, DC, parallel. The perpendicular, / ] EF, is called the altitnde. AFB The area of a trapezoid is equal to half the product of the svm of the two parallel sides by '.he altitnde (Bk, IV., Prop. VII.). Examples. 1. Required the area... | |
 | Evan Wilhelm Evans - Geometry - 1862 - 116 pages
...that the area of a triangle is equal to half the product of its base by its altitude. THEOREM XVIII. The area of a trapezoid is equal to half the product of the sum of its parallel sides by its altitude. Let ABCD be a trapezoid of I) which AB and DC are the parallel... | |
 | Eli Todd Tappan - Geometry, Modern - 1864 - 288 pages
...altitudes lO and DH, or as the squares of any homologous lines. AREA OF TRAPEZOIDS. 393. Theorem — The area of a trapezoid is equal to half the product of its altitude by the sum of its parallel sides. The trapezoid may be divided by a diagonal into two... | |
 | Charles Davies - Arithmetic - 1865 - 468 pages
...two of its opposite sides, / AB, DC, parallel. The perpendicular, / EF, is called the altitude. A ru The area of a trapezoid is equal to half the product of the sum of the two parallel sides by the altitude (Bk. IV., Prop. VII.). Examples. 1. Required the area... | |
 | Elias Loomis - Geometry - 1871 - 302 pages
...; and equivalent triangles, whose altitudes a« equal, have equi 1 bases. PROPOSITION VII. THEOREM. The area of a trapezoid is equal to half the product of itt altitude by the sum of its parallel sides. Let ABCD be a trapezoid, DE its altitude, AB and CD... | |
 | Eli Todd Tappan - Geometry - 1873 - 288 pages
...altitudes IO and DH, or as the squares of any homologous lines. AREA OF TRAPEZOIDS. 392. Theorem — The area of a trapezoid is equal to half the product of its altitude by the sum of its parallel sides. The trapezoid may be divided by a diagonal into two... | |
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The area of a trapezoid is equal to half the product of the sum of its bases by its altitude. A b B Given the trapezoid ABCD, with bases b and & 
