10.1 Circles
Name a diameter
AB
What is the measure of a major arc in a circle?
How many letters do you use to name it?
major arc measures greater than 180 degrees, 3 letters
What is the arc length formula? Use VOCAB words
L = (Central Angle/360) x Circumference
What is the area of sector formula? Use VOCAB words
A = (Central Angle/360) x Area of circle
Write a conditional statement for Theorem 1
Drawing a picture will help!
If arcs are congruent, then chords are congruent
Name a chord
AB or DE
What is true about the measure of a minor arc and measure of the central angle in a circle?
They are equal
Find the length of the arc (Exact Answer)
Central Angle = 120 degrees
Radius = 4.5
3pi
(pi = 3.1415...)
Find the Area of Sector (Exact Answer)
Central Angle = 300
Radius = 6
30pi
Write a conditional statement for Theorem 2
Drawing a picture will help!
If diameter is perpendicular to chord, then the chord and arcs are bisected
Name ALL radii (radius plural)
PA, PB, PC
What is the degree measure of a semicircle?
Draw a semicircle on your whiteboard.
180 degrees
Find the length of the arc (Exact Answer)
Central Angle = 315
Radius = 5
(35/4)pi
(pi = 3.1415...)
Find the Area of Sector (Exact Answer)
Central Angle = 330
Radius = 5
(275/12)pi
Write a conditional statement for Theorem 3
Drawing a picture will help!
If 2 chords are equidistant from center of circle, then those 2 chords are congruent
Circle P's circumference = 7.4 cm, What is the diameter?
(round to nearest hundredth)
2.36 cm
Slide 9
142 degrees
Find the length of the arc (Exact Answer)
Slide 11
14pi cm
Find the Area of the triangle
Slide 13
(49/2) = 24.5 km2
Slide 15
CD = 32
Slide 8
Approx 40.84 inches
13 x pi
Slide 10
232 degrees
52 + 38 + 142
Find the length of the arc (Exact Answer)
Slide 12
21pi cm
Find the Area of the shaded region (Exact Answer)
Slide 14
(49/4)pi - (49/2) km2
Slide 16
OB = 10
measure of arc AB = 56 degrees