Download Ray Vertex

Exploring Angle Relationships
Ray
O
Z
Y
Vertex
OZ
α
O
Z
An angle is the figure formed when
two rays meet at a common endpoint.
α
∠O
∠ YOZ
∠ ZOY
Sep 9-6:55 PM
1
Straight Angle
Right Angle
X
X
Y
W
Z
O
Y
W
Acute Angle
Obtuse Angle
X
X
Y
W
Z
O
Y
W
Z
O
Complementary Angles
Supplementary Angles
X
X
Y
W
Z
O
O
Z
Y
W
Sep 9-9:10 PM
O
Z
2
Estimating Angle Measures
Sketch a...
90o angle
45o angle
135o angle
How would you
sketch a...
60o angle
75o angle
Sep 9-9:24 PM
3
Remember congruent segments, sides, polygons...
Now we have congruent angles
Angles with equal measures
4
S
R
1
∠R ≅ ∠S
2
3
Vertical angles have equal measure
∠1 ≅ ∠3
∠2 ≅ ∠4
NOTE:
If you make the rays longer,
the angle is still the same!!
Angles formed by intersecting lines
and facing in opposite directions
Sep 9-9:33 PM
4
Acute Triangle: A triangle with all 3 acute (< 90o) angles
Obtuse Triangle: A triangle with 1 obtuse (> 90o) angle
o
Right Triangle: A triangle with 1 right (= 90 ) angle
25o
xo
100 o
140o
xo
Sep 14-7:46 AM
5