Area of Quadrilaterals and Circles and Sectors

What is/are the formula(s) to find the area of a circle?

• πr²

• 2πr

• √π

Find the area of the shaded sector of circle O.  The radius is 6 inches and the central angle is 100°.  Express answer to the nearest tenth of a square inch.

• 9.2 sq. in.

• 10.5 sq. in.

• 31.4 sq. in.

• 38.2 sq. in.

Find the area of the dark blue sector shown at the left.  The radius of the circle is 4 units and the length of the arc (the curved edge of the sector) measures 7.85 units.  Express answer to thenearest tenth of a square unit.

• 0.3 square units

• 15.7 square units

• 19.7 square units

• 50.3 square units

In circle O, the radius is 4, and the measure of minor arc AB is 120 degrees. Find the length of minor arc AB to the nearest integer.

• 5

• 9

• 8

• 6

Find the arc length.  Leave your answer in terms of π.

• 7/4π

• 7/2π

• 1/8π

• 45π

In circle O, the radius is 4, and the length of minor arc AB is 4.2 feet.  Find the measure of minor arc AB to the nearest degree.

• 90

• 60

• 55

• 113

A region bounded by two radii of the circle and their intercepted arc is a ....

• arc of a circle

• arc length of a circle

• sector of a circle

• segment of a circle

What is the arc length of minor arc AB?

• 5.23

• 103

• 33.33

• 50

What is the area of the shaded segment?

• 185.0619

• 88.9359

• 39.3078

• 5.7975

A ____ angle is an angle whose vertex is a the center of a circle.

• supplementary

• complimentary

• central

• obtuse