![altitude geometry definition trapezoid altitude geometry definition trapezoid](http://www-formula.com/images/Geometry/trapezoid/height-isosceles-trapezoid/height-isosceles-trapezoid-d.png)
The new trapezoid is upside down from how you usually see them, but don't let that stop you! The short base b is 21 inches long. So, with trapezoid L M N O, you could also have written the formula like:Ī r e a = 1 2 × 9 × ( 11 + 7 ) Example #2 Remember that multiplying by ½ is the same as dividing by 2, so you can add the lengths of the bases and then divide their sum by two, if that is easier for you.īecause of the commutative property of multiplication, you can rearrange these three numbers, 1 2, altitude h, and the length of bases a + b, in any order to make the calculation easy.
![altitude geometry definition trapezoid altitude geometry definition trapezoid](https://ph-static.z-dn.net/files/d00/a550ae0b7152b0772a96b386420ad361.png)
So a trapezoid measured in feet gives an area in square feet, centimeters yield square centimeters, and so on. What is the area in square meters?ĭid you get 81 square meters? Your answer for area is always in square units of the linear measurement. Now you try it! Another trapezoid has a long base a, 11 meters, and a shorter base b, 7 meters. The area of this trapezoid is 50 square centimeters. The height, h, is 5 cm.įirst, let's plug these numbers into our formula: We will label longer side N O as a and shorter side L M as b. Line segment L M is 7 cm long, and line segment N O is 13 cm long. Trapezoid L M N O has parallel bases L M and N O. We take half the sum of the length of the two bases (their average) and then multiply that by the altitude, or height, to find the area in square units. Multiplying times 1 2 is the same as dividing by 2. So, 12 books ÷ 3 people = an average of 4 books each. Together, 12 books are being held by 3 people. So if you have three people holding books, you can find the average number of books they are holding like this: Martin is holding 5 books, Mack is holding 3 books, and Maria is holding 4 books. In mathematics, an average is the sum of a group of numbers divided by the quantity of items in the group. A perpendicular line from the base to the other parallel side will give you the trapezoid's height or altitude.
![altitude geometry definition trapezoid altitude geometry definition trapezoid](https://www.geogebra.org/resource/fnBn7NQk/EkwqrAGmmuguBYTa/material-fnBn7NQk-thumb@l.png)
Usually the trapezoid is presented with the longer parallel side - the base - horizontal. The parallel sides are the trapezoid's two bases the other two sides are its legs. It has four line segments and four interior angles. So, this four-sided polygon is a plane figure and a closed shape. A trapezoid is a quadrilateral with one pair of parallel sides.