Warm Up 3/6 8 ft 7 ft 3 ft D C O 20x B A 25x ? 9m 18m 50m 1. Find the missing angles. If <LOM= 2x + 46 and < MON = 3x – 6 and they are complementary. (use the image at the right for visual help) 2. The image shows a wall of an apartment. You want to paint the wall. What’s the area? 11 ft 3. What is the constant of proportionality, k? 4. What is the measure of < BOA A volleyball court is a rectangle that is similar in shape to an Olympic sized pool. Find the width of the pool. 8 ft 7 ft 3 ft D C O 20x B A 25x ? 9m 18m 50m

Composite Area

Sept. 4! 1.7 Composite Figures A composite figure is formed from two or more figures. To find the area of a composite figure: Find the areas of each figure then add them up. To find the area of a shaded region, you need to subtract the areas.

Example #1: Find the area of the composite figure. The composite figure contains 2 triangles and 1 square. We need to find the area of each region. Area of 1 triangle: A = ½ bh A = ½ (7)(4) A = ½ (28) A = 14 yds2 Area of square: A = lw = 7(7) = 49 yd2 Total area of figure: Add up areas of 2 triangles and square: A = 2(14) + 49 = 28 + 49 = 77 yd2.

Add areas of square and semicircle: Example #2: Find the area of the figure. The figure contains: 1 square and a semicircle Area of square: A = lw = 6(6) = 36 ft2 Area of circle: A = r2 A = (3)2 = 9 ft2 Area of semicircle = ½ (9) = 4.5 ft2 3 ft. Total area of figure: Add areas of square and semicircle: A = 36 + 4.5 cm2

Diameter = Length of square = = 8 ft. Radius = ½ (8) = 4 ft. Example #3: Find the area of the shaded region if the area of the square is 64 ft2. We are given the area of the square, we need to find the area of the circle. What is its radius? Diameter = Length of square = = 8 ft. Radius = ½ (8) = 4 ft. Area of circle: A = r2 A = (4)2 = 16 ft2. d = 8 ft. Area of shaded region = Area of square – Area of circle A = 64 - 16 ft2.

QUIZ Show your work! 2. Find the area of the shaded region above. 20 cm 1. Find the area of the entire figure below. 2. Find the area of the shaded region above.

Today’s assignment (option 1) You will look over the tangram pictures and select one to replicate You will place it on a sheet of graph paper and trace each shape to show your picture You will use the graph lines to estimate the base and height of each shape (round to the nearest whole number) Find the area of your composite figures

Today’s assignment (option 2) You will create your name using block letters. You must use a minimum of 4 letters. So if your first name only has three letters then include your last name initial Your name must include at least 2 triangles 1 circle 1 trapezoid A parallelogram (the slanted rectangle) Find the area of each letter by drawing each shape that was created in the letters of your name. Write the formula for area for each shape. Solve

Monday 3/6 You have approximately 20 minutes to complete your tangram or name activity Once you are done use the notes from today to complete the worksheet on circumference (perimeter) and area of circles.