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Composite Figures. All in One. Composite figures. Composite figures are two or more basic figures that can be combined. 5 cm. Find the perimeter of this figure, which consists of a semicircle and a rectangle. 7 cm. 7 cm. 5 cm. P=l+l+w+ π d/2 P=(5)+(5)+(7)+ π (7)/2 P=17+21.99/2
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Composite Figures All in One
Composite figures Composite figures are two or more basic figures that can be combined. 5 cm Find the perimeter of this figure, which consists of a semicircle and a rectangle. 7 cm 7 cm 5 cm P=l+l+w+πd/2 P=(5)+(5)+(7)+π(7)/2 P=17+21.99/2 P=17+10.99 or 11 P=28cm2
Composite figures Now we need to find the perimeter of three sides of the rectangle at the bottom of the figure. Total Perimeter = Circumference of top + Perimeter of bottom = 11 cm + 17 cm = 28 cm
Problem Solution-we want to find the perimeter of the building. So we break the composite figure into three basic shapes-two rectangles and one square. 170 115 115 170 170 We find the length Of the indented part of Each rectangular shape By subtracting 170 cm From 210 cm to get 40 cm. 210 210 170 40 40 115 115 P = (115 + 210 + 115 + 40) + (170 + 170)+ (115 + 210 + 115 + 40) P = 1,300 cm
What is the perimeter of the composite figure? 4 cm 5 cm3 cm 4 cm 4 cm 3 cm5 cm • Find the lengths of the missing sides. Then add the side lengths. • Use the properties of congruent figures to find the missing measures. • The rectangle has a width of 4 cm. • The left side of the rectangle is 4 cm. • Add the lengths of the sides. • 5 cm + 3 cm + 4 cm + 4 cm + 5 cm + 3 cm + 4 cm + 4 cm = 32 cm • The perimeter of the figure is 32 cm. 4 cm • Hint: To determine the perimeter of a composite figure, measure the distance around the outside of the figure.
Bill is painting his basement floor. 2.3 m The dimensions are: 2.5 m If one can of paint will cover 3.5 m2, and each can of paint costs $15.25, what is his total cost? 3.2 m 1.8 m
a) Determine the total area. 2.3 m A1 Atotal = A1 + A2 2.5 m A = 2.3 x 2.5 + 3.1 x 1.5 A = 5.75 + 4.65 A2 3.2 m A = 10.4 m2 1.8 m
b) If one can of paint covers 3.5 m2, how many cans of paint will he need? 2.3 m 2.5 m 10.4 m2 3.2 m He will need about three cans of paint. 1.8 m