Page 138 - Math Course 1 (Book 2)

Geometric Area: Polygons and Circles

Real World Example
Next, f nd the height of the triangle, XS.
Since m∠XZY is 60, XS = 3.5
√3(√3) or 10.5 A swimming pool company manufactures circular
covers for above ground pools. If the cover is 10
inches longer than the pool on each side, f nd the
1 area of the cover in square yards.
A = bh Area of a triangle
2
A. 31.0 yd 2
1 2
= (7√3)(10.5) b = 7√3, h = 10.5 B. 33.8 yd
2 C. 1215.1 yd 2
D. 43743.5 yd 2
≈ 63.7 Use a calculator.
X

Answer

Y Z

The area of the shaded
region is 153.9 – 63.7 or
Answer
90.3 square centimeters
to the nearest tenth.

Area of an Inscribed Polygon
Your Turn! Find the area of the shaded region. Assume that
the triangle is equilateral. Round to the nearest
Area of a Regular Polygon tenth.

Find the area of a regular pentagon with a A. 32.5 in 2
perimeter of 120 inches. To the nearest square B. 78.5 in 2
inch. C. 13.6 in 2
D. 46.1 in 2
A. 890 in 2
B. 1225 in 2
C. 991 in 2
D. 1982 in 2

Answer
Answer

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