Perimeter

Learning Objectives Calculate the perimeter of various polygons (triangles, quadrilaterals, regular polygons). Determine the circumference of circles given radius or diameter. Find the perimeter of composite figures by identifying and summing all exterior side lengths. Solve real-world problems involving perimeter and circumference. Apply algebraic expressions to represent and calculate perimeter for unknown side lengths. Utilize the Pythagorean theorem to find unknown side lengths required for perimeter calculations. Ever wondered how much fencing you'd need to enclose your backyard, or the distance you'd walk around a circular track? 🏃‍♀️ That's perimeter in action! In this lesson, you'll learn how to measure the total distance around the outside of a...

TermDefinitionExample PerimeterThe total distance around the outside of a two-dimensional shape.If you walk along all the edges of a rectangular park, the total distance you walk is the park's perimeter. PolygonA closed two-dimensional shape made up of straight line segments.Triangles, squares, rectangles, and hexagons are all polygons. CircumferenceThe perimeter of a circle.The distance around the edge of a bicycle wheel is its circumference. DimensionsThe measurements of length, width, or height of a shape. For perimeter, these refer to the lengths of the sides.A rectangle might have dimensions of 10 cm length and 5 cm width. Composite FigureA shape made up of two or more basic geometric shapes joined together.An L-shaped room can be viewed as two rectangles combined. Regular Polyg...

Perimeter of any Polygon $P = s_1 + s_2 + s_3 + \dots + s_n$ To find the perimeter of any polygon, sum the lengths of all its exterior sides. Perimeter of a Rectangle $P = 2l + 2w$ or $P = 2(l+w)$ For a rectangle with length $l$ and width $w$, the perimeter is twice the length plus twice the width. Perimeter of a Square $P = 4s$ For a square with side length $s$, the perimeter is four times the side length. Circumference of a Circle $C = \pi d$ or $C = 2\pi r$ For a circle with diameter $d$ or radius $r$, the circumference is pi ($\pi \approx 3.14159$) times the diameter, or two times pi times the radius.