Chapter Area, Pythagorean Theorem, and Volume 14 Copyright © 2013, 2010, and 2007, Pearson Education, Inc.
14-1 Areas of Polygons and Circles Areas on a Geoboard Converting Units of Area Land Measure Area of a Rectangle Area of a Parallelogram Area of a Triangle Area of a Kite Area of a Trapezoid Area of a Regular Polygon Area of a Circle Area of a Sector Copyright © 2013, 2010, and 2007, Pearson Education, Inc.
Areas on a Geoboard Addition method divide an area into smaller pieces and then add the areas. What is the area of this figure? 19 square units Copyright © 2013, 2010, and 2007, Pearson Education, Inc.
Rectangle method – construct a rectangle encompassing the entire figure and then subtract the areas of the unshaded regions. Area = 16 – ( ) = 9 Copyright © 2013, 2010, and 2007, Pearson Education, Inc.
Example 14-1 Find the area of the figure. Copyright © 2013, 2010, and 2007, Pearson Education, Inc.
Example 14-1 The area of the hexagon equals the area of the surrounding rectangle minus the sum of the areas of figures a, b, c, d, e, f, and g. Copyright © 2013, 2010, and 2007, Pearson Education, Inc.
Converting Metric Units of Area UnitSymbol Relationship to Square Meter square kilometerkm 2 1,000,000 m 2 square hectometerhm 2 10,000 m 2 square dekameterdam m 2 square meterm2m2 base unit square decimeterdm m 2 square centimetercm m 2 square millimetermm m 2 Copyright © 2013, 2010, and 2007, Pearson Education, Inc.
Convert each of the following: a.5 cm 2 to mm 2 Example 14-2 b. 124,000,000 m 2 to km 2 Copyright © 2013, 2010, and 2007, Pearson Education, Inc.
UnitEquivalent of Other Units 1 ft in. 2 or yd 2 1 yd 2 9 ft 2 1 mi 2 3,097,600 yd 2 or 27,878,400 ft 2 Converting English Units of Area Copyright © 2013, 2010, and 2007, Pearson Education, Inc.
Land Measure English units acre square mile Metric units are hectare square kilometer Copyright © 2013, 2010, and 2007, Pearson Education, Inc.
Unit of AreaEquivalent of Other Units 1 a100 m 2 1 ha100 a, or 10,000 m 2, or 1 hm 2 1 km 2 1,000,000 m 2 1 acre4840 yd 2 1 mi acres Land Measure Copyright © 2013, 2010, and 2007, Pearson Education, Inc.
a.A square field has a side of 400 m. Find the area of the field in hectares. Example 14-3 b. A square field has a side of 400 yd. Find the area of the field in acres. Copyright © 2013, 2010, and 2007, Pearson Education, Inc.
Area of a Rectangle A = ℓw Copyright © 2013, 2010, and 2007, Pearson Education, Inc.
Area of a Parallelogram A = base x height = bh = ag Copyright © 2013, 2010, and 2007, Pearson Education, Inc.
Area of a Triangle Copyright © 2013, 2010, and 2007, Pearson Education, Inc.
Find the areas: 40 cm 2 4 cm 2 20 cm 2 Example 14-5 Copyright © 2013, 2010, and 2007, Pearson Education, Inc.
Area of a Kite The area of a kite can be found by relating it to the area of a rectangle. Copyright © 2013, 2010, and 2007, Pearson Education, Inc.
Area of a Trapezoid Copyright © 2013, 2010, and 2007, Pearson Education, Inc.
Example 14-6 Find the area of each trapezoid. 56 cm 2 15 cm 2 Copyright © 2013, 2010, and 2007, Pearson Education, Inc.
Area of a Regular Polygon Copyright © 2013, 2010, and 2007, Pearson Education, Inc.
Area of a Circle Copyright © 2013, 2010, and 2007, Pearson Education, Inc.
Area of a Sector Copyright © 2013, 2010, and 2007, Pearson Education, Inc.