Equations of Circles
Circumference & Area
Sectors
Circle Graphs
100

What is the equation of the circle whose radius is 3 square root of 7 and whose center is (-4, 3)?

(x+4)2+(y-3)2=63

100

The area of a circle with radius 6 cm is how many times larger than the area of a circle with radius 2?

9 times larger

100

A circle with diameter 8 cm is divided into 8 equal sectors.  What is the arc length and area of one sector?

Arc length is 1 pi cm.  Area of sector is 2 pi cm2.

100

In figure F, what would be the central angle for the sector labeled "Nike"?

115.2 degrees

200

What is the equation of a circle whose circumference is 16pi and whose center is (-3,-1)?

(x+3)2+(y+1)2=64

200

A circle has a radius = the square root of 10.  What is the diameter, circumference, and area of the circle?

The diameter is 2 square root of 10.

The circumference is 2 pi square root of 10.

The area is 10 pi.

200

The circle in Figure D is divided into 4 equal sectors.  The length of arc DAC is 12 pi.  Find the central angle of one sector and the area of one sector.

The central angle is 90 degrees.  The area of one sector is 16 pi.

200

If a person's monthly budget is $4,000, how much would he spend on groceries and clothes?

$880

300

What is the center and diameter of a circle whose equation is x2+(y-5)2=48 ?

Center is (0,5) and diameter is 8 square root of 3.

300

What is the circumference and area of a circle whose equation is (x-4)2+(y+8)2=75?

Circumference is 10 pi roots of 3.

Area is 75 pi.

300
In figure C, the length of arc AB is 10 pi.  What is the radius and diameter of the circle.

The radius is 12 and the diameter is 24.

300

If there were 40,000 sneakers sold this month, how many are Reebok?  (Figure F)

6,000 Reebok

400

What is the equation of a circle with center (2,-4) and passes through the point (4, -9)?

(x-2)2+(y+4)2=29

400

What is the area of a circle that has a circumference of 15 inches?  (Show complete work, including formulas.) Round to the nearest tenth.

17.9 square inches

400

In figure E, what is the EXACT perimeter of the shaded sector? 

6 pi + 10

400

What is the center and radius of the circle in figure B?

Center is (8,5) and radius is 4.

500

What is the equation of a circle whose diameter has endpoints (2,-1) and (6,1)?  

(x-4)2+y2=5

500

What is the circumference of a circle that has an area of 70 inches? (Show complete work, including formulas.)  Round to the nearest tenth

29.7 inches

500

A regular octagon is inscribed in a circle of radius 16 inches.  Starting at point A, a 52 pi inch string is wrapped clockwise around the circle.  

At which point will the string end?  

Point F

500

What is the equation of the circle in figure A?

(x-5)2+(y-4)2=9