Perimeter, Area, and Volume SOL 5.8b Plane figure – any flat, closed shape. Polygon – a closed plane figure composed of at least three line segments that do not cross. Perimeter is the path or distance around any plan figure. It is a measure of length. - When you think perimeter, think of the word AROUND (1) Examples of Perimeter: 1. A fence AROUND your house. 2. The blue tiles AROUND the classroom. 3. A border AROUND the bulletin board. Area is the surface included within a plan figure. Area is measured by the number of square units needed to cover a surface or plane figure. - When you think area, think of the words COVER UP (2). Examples of Area: 1. COVERING UP your yard with grass. 2. COVERING UP a wall with paint. 3. COVERING UP a bulletin board with paper. Volume of a three-dimensional figure is a measure of capacity and is measured in cubic units. - When you think volume, think of the words FILL UP (3). Examples of Volume: 1. FILLING UP a box with presents. 2. FILLING UP an iPad cart with iPads. 3. FILLING UP a pencil box with supplies. Finding Perimeter, Area, and Volume SOL 5.8a Perimeter of any Polygon - To determine the perimeter of any polygon add (+) the lengths of the sides. - Don’t forget to include the measurement label provided! Examples: A square with 4 in. sides = 16 in. A rectangle with length of 8 ft. and width of 2 ft. = 20 ft. Area of a Square or Rectangle - To determine area, multiply the length of the base by the length of the height. - Don’t forget – area is labeled in square units, so you must include that in your measurement label! Examples: A square with a side of 3 cm = 9 cm2 A rectangle with length of 10 mm and width of 4 mm = 40 mm2 Area of a Right Triangle - A right triangle has one right angle. - To determine area, multiply the base by the height, and then half (÷2) your answer. - Don’t forget – area is labeled in square units, so you must include that in your measurement labe! Examples: A right triangle with base of 6 yds and height of 2 yds = 6 yd2 Volume of a Rectangular Prism or Cube - A rectangular prism or cube is a three-dimensional figure. - To determine volume, multiply the length by the width by the height. - Volume is labeled in cubic units so you must include that in your measurement label! Examples: A cube with sides of 5 m = 125 m3 .