Click the mouse button or press the Space Bar to display the answers. Transparency 11-2 5-Minute Check on Lesson 11-1 Find the area and the perimeter of each parallelogram. Round to the nearest tenth if necessary. 2. 3. 4. TRY: Find the height and base of this parallelogram if the area is 168 square units 11 cm 13 cm 45° 17 ft 12 ft 6.3 m 60° 11 in 18 in x + 2 x Click the mouse button or press the Space Bar to display the answers.

Lesson 11-2 Day 1 Areas of Triangles

Area of Triangles A = ½ * b * h h is height (altitude) Triangle Area A = ½ * b * h h is height (altitude) b is base (┴ to h) h S T W

EXAMPLE 1 R Find the area of triangle RST h 45° S T 10 W 10

EXAMPLE 2 Find the area of quadrilateral ABCD if AC = 35, BF = 18, and DE = 10. Example 2-1a

EXAMPLE 3 Find the area of quadrilateral HIJK if IK = 16, HL = 5 and JM = 9 Example 2-1b

EXAMPLE 4 Find the area of the triangle whose vertices are (3,6), (7,6) and (3,1).

EXAMPLE 5 Find the area of the parallelogram whose vertices are (0,0), (4,0), (5,5), and (1,5)

Summary & Homework Summary: Classwork: YOU MUST SHOW WORK!!!!! The formula for the area of a triangle can be used to find the areas of many different figures Congruent figures have equal areas Classwork: YOU MUST SHOW WORK!!!!! pg 605 (5,13, 14, 19, 20, 34, 35) pg 599 (21-25 and page 605 #7) Plot points first then find the area of each!!!