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The document covers key concepts in geometry, focusing on calculating areas of various shapes including parallelograms, triangles, and trapezoids. It also explores how changes in dimensions affect perimeter and area, and introduces methods for working with polygons on coordinate planes and composite figures.

• **How to find the area of a parallelogram formula** is introduced, along with definitions of polygons and special quadrilaterals.

• **How to find the area of a triangle** is explained using the formula A = 1/2 bh.

• The **area of trapezoid** formula A = 1/2h(b₁ + b₂) is presented with examples.

• Effects of dimension changes on perimeter and area are discussed.

• Techniques for finding perimeter and area on coordinate planes are covered.

• Methods for calculating areas of composite and overlapping figures are introduced.