Embed Size (px)
Citation preview
1. Find the area of a regular hexagon with side length of 8 centimeters. Round to the nearest tenth if necessary.
2. Find the area of a square with an apothem length of 14 inches. Round to the nearest tenth if necessary.
3. Find the area of a regular triangle with side length of 18.6 meters. Round to the nearest tenth if necessary.
4. Find the area of the shaded region
to the nearest tenth. Assume that
the polygon is regular.
• composite figure
• Find areas of composite figures.
• Find areas of composite figures on the coordinate plane.
What is the area of the composite figure? Round to the nearest tenth.
A 713.1 ft2
B 852.5 ft2
C 953.1 ft2
D 992 ft2
Area of a Composite Figure
Read the Item
The figure can be separated into a rectangle with dimensions 16 feet by 32 feet, a triangle with a base of 32 feet and a height of 15 feet, and two semicircles with radii of 8 feet.
Solve the Item
Answer: The area of the composite figure is 953.1 square feet to the nearest tenth. The correct answer is C.
Area of a Composite Figure
Area formulas
Substitution
Simplify.
Use a calculator.
Area of composite figure
A. A
B. B
C. C
D. D
A. 478.5 ft2
B. 311.2 ft2
C. 351.2 ft2
D. 438.5 ft2
Find the area of the figure in square feet. Round to the nearest tenth if necessary.
A rectangular rose garden is centered in a border of lawn. Find the area of the lawn around the garden in square feet.
The length of the entire lawn is 25 + 100 + 25 or 150 feet. The width of the entire lawn is 25 + 20 + 25 or 70 feet. The length of the rose garden is 100 feet and the width is 20 feet.
Find the Area of a Composite Figure to Solve a Problem
Answer: The area of the lawn around the garden is 8500 square feet.
Find the Area of a Composite Figure to Solve a Problem
Simplify.
Substitution
Simplify.
Area formulas
area of composite figure
– area of rose garden
1. A
2. B
3. C
4. D
A. 168 ft2
B. 156 ft2
C. 204 ft2
D. 180 ft2
INTERIOR DESIGN Cara wants to wallpaper one wall of her family room. She has a fireplace in the center of the wall. Find the area of the wall around the fireplace.
Coordinate Plane
Find the area of polygon MNPQR.
First, separate the figure into regions. Draw an auxiliary line perpendicular to from M (we will call this point S), an auxiliary line from N to the x-axis (we will call this point K), and an auxiliary line from P to the Origin, O.
This divides the figure into triangle MRS, triangle NKM, trapezoid POKN and trapezoid PQSO.
Coordinate Plane
Now, find the area of each of the figures.
Find the difference between y-coordinates to find the lengths of the bases of the triangles and the lengths of the bases of the trapezoids.
Find the difference between x-coordinates to find the heights of the triangles and trapezoids.
Coordinate Plane
Answer: The area of polygon MNPQR is 44.5 square units.
Simplify.
Substitution
Area formulas
Δ Δ
1. A
2. B
3. C
4. D
A. 38 units2
B. 17 units2
C. 15 units2
D. 19 units2
Find the area of polygon ABCDE.
