Perimeter is the distance around the outside of a shape. It is the total length of all the sides of the shape added together. The perimeter is measured in units such as inches, feet, meters, or centimeters, depending on the scale of the shape.

The formulas for finding the perimeter of common shapes are:

**Square:**Perimeter = 4 * side length**Rectangle:**Perimeter = 2 * (length + width)**Triangle:**Perimeter = side1 + side2 + side3**Circle:**Perimeter = 2 * π * radius (or π * diameter)

Let's solve some example problems to practice finding the perimeter of different shapes:

- Find the perimeter of a square with side length 5 units.
- Find the perimeter of a rectangle with length 7 units and width 4 units.
- Find the perimeter of a triangle with side lengths 3 units, 4 units, and 5 units.
- Find the perimeter of a circle with a radius of 8 units.

Perimeter = 4 * 5 = 20 units

Perimeter = 2 * (7 + 4) = 2 * 11 = 22 units

Perimeter = 3 + 4 + 5 = 12 units

Perimeter = 2 * π * 8 = 16π units

Here are some tips for studying and mastering the concept of perimeter:

- Practice using the formulas for finding the perimeter of different shapes.
- Draw and label different shapes to visualize the concept of perimeter.
- Work on a variety of example problems to strengthen your understanding.
- Use real-life examples to understand the practical application of perimeter in measuring boundaries and distances.
- Review and memorize the perimeter formulas for common shapes.

By understanding the concept of perimeter and practicing with different shapes, you can become proficient in calculating the perimeter of various geometric figures.

.Study GuideSimilarity and scale Worksheet/Answer key

Similarity and scale Worksheet/Answer key

Similarity and scale Worksheet/Answer key

Similarity and scale Worksheet/Answer keyUsing Similar Polygons Worksheet/Answer keySimilar Polygons Worksheet/Answer keyUsing Similar Polygons Worksheet/Answer keySimilar Polygons

Number and Operations (NCTM)

Understand numbers, ways of representing numbers, relationships among numbers, and number systems.

Understand and use ratios and proportions to represent quantitative relationships.

Compute fluently and make reasonable estimates.

Develop, analyze, and explain methods for solving problems involving proportions, such as scaling and finding equivalent ratios.

Geometry (NCTM)

Analyze characteristics and properties of two- and three-dimensional geometric shapes and develop mathematical arguments about geometric relationships.

Understand relationships among the angles, side lengths, perimeters, areas, and volumes of similar objects.

Create and critique inductive and deductive arguments concerning geometric ideas and relationships, such as congruence, similarity, and the Pythagorean relationship.

Apply transformations and use symmetry to analyze mathematical situations.

Describe sizes, positions, and orientations of shapes under informal transformations such as flips, turns, slides, and scaling.

Measurement (NCTM)

Apply appropriate techniques, tools, and formulas to determine measurements.

Solve problems involving scale factors, using ratio and proportion.

Grade 8 Curriculum Focal Points (NCTM)

Geometry and Measurement: Analyzing two- and three-dimensional space and figures by using distance and angle

Students use fundamental facts about distance and angles to describe and analyze figures and situations in two- and three-dimensional space and to solve problems, including those with multiple steps. They prove that particular configurations of lines give rise to similar triangles because of the congruent angles created when a transversal cuts parallel lines. Students apply this reasoning about similar triangles to solve a variety of problems, including those that ask them to find heights and distances. They use facts about the angles that are created when a transversal cuts parallel lines to explain why the sum of the measures of the angles in a triangle is 180 degrees, and they apply this fact about triangles to find unknown measures of angles. Students explain why the Pythagorean Theorem is valid by using a variety of methods - for example, by decomposing a square in two different ways. They apply the Pythagorean Theorem to find distances between points in the Cartesian coordinate plane to measure lengths and analyze polygons and polyhedra.