| James Stewart Eaton - Arithmetic - 1873 - 340 pages
...upon it, from the other angles of the trapezium, 6 and 8 inches ? Ans. 140 sq. in. 389. PROBLEM 3. **To find the area of a trapezoid : RULE. Multiply half the sum of the** parallel sides by the altitude, and the product will be the area. 387. What it a Quadrilateral ? How... | |
| Emerson Elbridge White - Arithmetic - 1870 - 350 pages
...altitude. 4. To find the area of any quadrilateral having two sides parallel, Multiply one half of **the sum of the two parallel sides by the perpendicular distance between them.** 5. To find the circumference of a circle, 1. Multiply the diameter by 3.1416. Or, 2. Divide the area... | |
| William John Macquorn Rankine, Edward Fisher Bamber - Mechanical engineering - 1873 - 368 pages
...by a pair of parallel straight lines, and a pair of straight lines not parallel). Multiply the half **sum of the two parallel sides by the perpendicular distance between them.** 32. Triangle. Rule A. — Multiply the length of any one of the sides by one-half of its perpendicular... | |
| William John Macquorn Rankine, Edward Fisher Bamber - Mechanical engineering - 1873 - 370 pages
...by a pair of parallel straight lines, and a pair of straight lines not parallel). Multiply the half **sum of the two parallel sides by the perpendicular distance between them.** 32. Triangle. Rule A. — Multiply the length of any one of the sides by one-half of its perpendicular... | |
| Philotus Dean - Arithmetic - 1874 - 472 pages
...rd. 4. What is the area of a triangle whose sides are, respectively, 18, 20, and 24 inches? Art. 473. **To find the area of a trapezoid. Rule. — Multiply half the sum of the** parallel sides by the altitude. Í. How many square feet in a board 18 ft. long, 18 in. wide at one... | |
| Mechanical engineering - 1874 - 1182 pages
...by 2, will be the area of the trapezium. To find the area of a trapezoid. — RULE 1. — Multiply **the sum of the two parallel sides by the perpendicular distance between them,** and half the product will be the area. RULE 2. — Draw a diagonal, to divide the trapezoid into two... | |
| James Stewart Eaton - Arithmetic - 1876 - 366 pages
...upon it, from the other anglea of the trapezium, 6 and 8 inches ? Ans. 140 sq. in. 389. PKOBLEM 3. **To find the area of a trapezoid : RULE. Multiply half the sum of the** parallel sides by the altitude, and the product will be the area. 387. What is a Quadrilateral ? How... | |
| Samuel Mecutchen, George Mornton Sayre - Arithmetic - 1877 - 200 pages
...5. The base of a rhomboid is 375 ft. 6 in., and the perpendicular height 40 yards; what is its area? **To find the area of a trapezoid. RULE. Multiply half the sum of the** parallel sides by the altitude. 1. What is the number of square feet in a trapezoid, one of the parallel... | |
| Moffatt and Paige - 1879 - 506 pages
...Trapezoid. A trapezoid is a quadrilateral figure having two only of its sides parallel. Rule. — Multiply **the sum of the two parallel sides by the perpendicular distance between them,** and take half the product for the. area. C __ A D f - E --- B Proof. — Let ACDB be a trapezoid, having... | |
| Joseph Ray - Arithmetic - 1880 - 420 pages
...II. To find the area of a triangle. Rule.— Take half the product of the base by the altitude. III. **To find the area of a trapezoid. Rule. — Multiply half the sum of the** parallel sides by the altitude. NOTE. — The following is demonstrated in Geometry : IV. To find the... | |
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