GEOMETRY Chapter 11 11 2 Areas of Regular

GEOMETRY: Chapter 11 11. 2 Areas of Regular Polygons

Postulate 24: Area of a Square Postulate The area of a square is the square of the length of its side. A = s 2

Postulate 25: Area Congruence Postulate If two polygons are congruent, then they have the same area. Postulate 26: Area Addition Postulate The area of a region is the sum of the areas of its nonoverlapping parts.

Theorem 11. 1: Area of a Rectangle The area of a rectangle is the product of its base and height. A = bh h b

Theorem 11. 2: Area of a Parallelogram The area of a parallelogram is the product of a base and its corresponding height. Images taken from: Geometry. Mc. Dougal Littell: Boston, 2007. P. 721.

Theorem 11. 3: Area of a Triangle The area of a triangle is one half the product of a base and its corresponding height. Images taken from: Geometry. Mc. Dougal Littell: Boston, 2007. P. 721.

Ex. 1. Find the area of the parallelogram RSTU. Images taken from: Geometry. Mc. Dougal Littell: Boston, 2007. P. 721.

Ex. 1. Find the area of the parallelogram RSTU. Answer: 700 square units Images taken from: Geometry. Mc. Dougal Littell: Boston, 2007. P. 721.

Ex. 2. The base of a triangle is one half the height. The area of the triangle is 64 square centimeters. Find the base and height.

Ex. 2. The base of a triangle is one half the height. The area of the triangle is 64 square centimeters. Find the base and height. Answer: 8 cm; 16 cm

Ex. 3 You need to buy paint so you can cover the back of an A-frame house and the top of a deck. A gallon of paint covers 275 square feet. How many gallons should you buy. Images taken from: Geometry. Mc. Dougal Littell: Boston, 2007. P. 722.

Ex. 3 You need to buy paint so you can cover the back of an A-frame house and the top of a deck. A gallon of paint covers 275 square feet. How many gallons should you buy. Answer: 3 gal Images taken from: Geometry. Mc. Dougal Littell: Boston, 2007. P. 722.

11. 2, p. 723, #1, 3 -8 all, 12 -18 all, 23 -27 odds (16 questions)