warm up. review hw skills check p a b case i: central angle: vertex is at the center
TRANSCRIPT
Warm up
Review HW
Skills Check
P
A
B
Central ANGLE = ARC
Case I: Central Angle: Vertex is AT the center
Case II: Inscribed Angle: Vertex is ON circle
ANGLE = ARC
2ANGLE
ARCANGLE
ARC
2
ArcdIntercepteAngleInscribed
160
80
The arc is twice as big as the angle!!
120
x
y
Find the value of x and y
Examples1. If mJK = 80 and JMK = 2x – 4, find x.
M
Q
K
S
J
2. If mMKS = 56, find m MS.
x = 22
112
72˚
If two inscribed angles intercept the same arc, then they are congruent.
Find the measure of DOG and DIG D
O
G
I
If all the vertices of a polygon touch the edge of the circle, the polygon is INSCRIBED and the circle is CIRCUMSCRIBED.
a quadrilateral inscribed in a circle: opposite angles are
supplementary.A B
CD
180 CmAm180 DmBm
If a right triangle is inscribed in a circle then the hypotenuse is the diameter of the circle.
diameter
Example 3
In J, m3 = 5x and m 4 = 2x + 9.Find the value of x.
3
Q
D
JT
U
4
x = 3
4x – 14 = 90
H
K
GN
Example 4
In K, GH is a diameter and mGNH = 4x – 14. Find the value of x.
x = 26
Bonus: What type of triangle is this? Why?
z
y
110
85
110 + y =180y = 70
z + 85 = 180z = 95
Example 5 Find y and z.
Practice WS
Get in your groups please.
12 problems
Homework WS
Day 21 Inscribed
Angles
Choose even or odd problems