Parts of a Circle
Area & Circumference
Angles in a Circle
Equations of a Circle
Mixed Review
100

This is a segment that has endpoint on the center of the circle and the circumference.

Radius

100

What are both of the formulas for circumference?

C = 2*pi*r

C = pi*d

100

True or False: A central angle is equal to it's intercepted arc's measure.

True!

100

Write an equation: Center: (4,5) Radius = 3

(x - 4)2 + (y - 5)2 = 9

100

Can someone please tell me the difference between arc measure & arc length?!

Arc measure is in DEGREES. Arc length is in units (cm, in, yd... depends on the radius.) You need a formula to solve for arc length.

200

This is the location at which the tangent line intersects the circle.

Point of Tangency 

200

In terms of pi... What is the circumference of a circle whose radius is 8?

16 pi

200

What's the relationship between an inscribed angle and it's intercepted arc?

Inscribed angle is HALF the arc measure.

200

Write an equation: Center (-3, 8) Radius = 13

(x + 3)2 + (y - 8)2 = 169

200

How can we tell if a tangent line is perpendicular to a radius?

Pythag

300

You use this point to name a circle.

Center

300

In terms of pi... What is the area of a circle whose radius is 9?

81 pi

300

An inscribed angle that intercepts the diameter creates what kind of angle?

Right angle. 90 degrees

300

Write an equation: Center (9, 0) Radius = 

sqrt 75

(x - 9)2 + y2 = 75

300

Do the following sides form a right triangle?

13.2 in, 15.2 in, 20.5 in

No... if you type it into your calculator it will come out as false!

400

True or False: A diameter is a chord.

True

400

In terms of pi... What is the area of a circle whose diameter is 20?

100 pi

400

If two inscribed angles share the same intercepted arc, then those two angles are ____________.

Congruent

400

Write an equation: Center (0, 0) Diameter = 18

x2 + y2 = 81

400

If tangents meet at an external point, then those line segments are __________.

Congruent!

500

Recall two parts of a circle that you can name with three letters.

Semicircle, major arc, central angle, & inscribed angle.

500

Might need calculator or scrap paper.

A circle's circumference is 56 in. What is it's radius? Use 3.14 for pi.

r = 8.917 inches

500

What is the measure of arc ST?

45 degrees

500

Write an equation: Center: (-5, 7) radius: 

sqrt12

(x + 5)+ (y - 7)2 = 12

500

What is the formula for arc length?

l = x * C /360

M
e
n
u