10-1 Areas of Parallelograms and Triangles
Objective
To find the area of parallelograms and triangles
Dynamic Activity
Area of Parallelograms and Triangles
Lesson Vocabulary
- base of a parallelogram
- altitude of a parallelogram
- height of a parallelogram
- base of a triangle
- height of a triangle
Essential Understanding You can find the area of a parallelogram or a triangle when you know the length of its base and its height.
A parallelogram with the same base and height as a rectangle has the same area as the rectangle.
Take note Theorem 10-1: Area of a Rectangle
The area of a rectangle is the product of its base and height.
Theorem 10-2 Area of a Parallelogram
The area of a parallelogram is the product of a base and the corresponding height.
A base of a parallelogram can be any one of its sides. The corresponding altitude is a segment perpendicular to the line containing that base, drawn from the side opposite the base. The height is the length of an altitude.
Table of Contents
- 6-1 The Polygon Angle-Sum Theorems
- 6-2 Properties of Parallelograms
- 6-3 Proving That a Quadrilateral Is a Parallelogram
- 6-4 Properties of Rhombuses, Rectangles, and Squares
- 6-5 Conditions for Rhombuses, Rectangles, and Squares
- 6-6 Trapezoids and Kites
- 6-7 Polygons in the Coordinate Plane
- 6-8 and 6-9 Coordinate Geometry and Coordinate Proofs