Circles+&+Polygons


 * UNIT: Circles and Polygons**

I. **Learning Objective:** The student will:

Find the perimeter of a polygon. Identify and find the radius, diameter and circumference of a circle. Find the area of rectangles, parallelograms, triangles and trapezoids. Find area of circles. Decide whether perimeter, circumference or area must be calculated to solve a given problem. Recognize when a problem has no solution. Identify corresponding parts of congruent figures. Recognize similar polygons and use corresponding sides to find unknown lengths. Use similar triangles to find an unknown measurement that cannot be measured directly. Find the square root of a number using a table or a calculator. Use the Pythagorean Theorem to find unknown lengths. Simplify square roots using the product property of square roots.

Perimeter Circles and circumference Area of polygons Area of circles Choosing perimeter, circumference, or area Problems with no solutions Congruent polygons Similar polygons Indirect measurement Square roots The Pythagorean Theorem Simplifying Square Roots Honors: Enrichment/acceleration/higher-level problems **Applicable Academic Standards:** 2.1.8 A, D, G 2.5.8 A, B, C, D 2.2.8 B, E, F 2.8.8 A, B, C, D, J 2.3.8 A, D, E 2.9.8 D, F, G 2.4.8 A, B, D, F
 * Content:**


 * Word problems/real-life situations may be used.
 * The drawing of a circle may be included.
 * The value of "pi" will be 3.14.
 * Any representation of a rational number may be used for the dimension of the circle.
 * The formulas will be given on the reference page.

Sample problems from Item Specs [|Content Standard 9.ppt]

Pi Day (March 14 or 3/14) is a great day to study circles.

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The 6th grade AMSTI unit Covering and Surrounding has an investigation of these topics that is wonderful.

Links
[|Discovering the Value of Pi] The students use a Java Applet[|1] to discover the fact that the ratio of the circumference to the diameter is a constant that applies to all circles. In other words, it teaches them the concept of pi and how it is derived. The lesson also includes a sheet with interesting facts about pi.

[|4 2 explore Pi page] Collection of links activities concerning Pi.