Slide1 : Measurement By Rosi Barron Area <--- To Teacher Page
Slide2 : • Fifth Grade Measurement: Measuring Area • Tips: -Teachers, please read through the whole presentation prior to the activity. -Each activity is meant to be used in addition to your classroom teaching. -Each activity includes a journal component. • Objectives: TSW determine the appropriate method to find the area of a figure.
Slide3 : Area: The number of square units needed to cover a surface. Methods of finding Area:
Rectangle - opposite sides are equal - Area = length x width OR A = l x w.
Triangle - a 3-sided figure - Area = ½ x base x height OR A = ½ x b x h.
Parallelogram - a quadrilateral with opposite sides parallel & congruent - a combination of a rectangle and 2 triangles - move 1 triangle to make a larger rectangle. <--- To Teacher Page
Slide4 : Choose the appropriate method to find the area of each of these figures. Record your answers-----> Remember your answers must be labeled cm². Why? A. B. Figure A: a rectangle with a length of 12 cm. and a height of 6 cm. Figure B: a triangle with a height of 8 cm. and a base of 5 cm.
Slide5 : Answers: More practice ---> A. B. Figure A is a rectangle so the area would equal to its length x its width OR A = 12 x 6 SO A = 72 cm² 12 cm. 6 cm. Figure is a triangle so the area would equal its base x its height OR
A = ½ x 5 x 8 A = ½ x 40 A = 20 cm²
Slide6 : Find the area of this Parallelogram. Remember, it is a combination of a rectangle and 2 triangles. How do you begin? Does this help? <---------- 15 cm. -----------> <------ 10 cm. ------> 8 cm. One more HINT -------->
Slide7 : <---------- 15 cm. -----------> <------ 10 cm. ------> 8 cm. a. b. c. a. b. c. Separate the parallelogram into 3 pieces, 2 triangles & 1 rectangle. Now move 1 triangle so you will have just 1 large rectangle. Each piece has been labeled.
Slide8 : <---------- 15 cm. -----------> Did you change this . . . <------ 10 cm. ------> a. b. c. 8 cm. <------ 10 cm. ------> a. b. 8 cm. <---------- 15 cm. -----------> c. To this? -----> What was that method of finding area for this figure? ---------->
Slide9 : <------ 10 cm. ------> a. b. 8 cm. <---------- 15 cm. -----------> c. Rectangle - opposite sides are equal - Area = length x width OR A = l x w. Area = 15 cm. X 8 cm.
Area = 120 cm² Figure out another way of finding out the area of this parallelogram. HINT: Think of them as 3 separate objects or 2 separate objects. Answers may vary.