Download Poolroom Math and Widgets

Poolroom Math and Widgets
Section 1.2 and 1.3
Angles
What is an angle? What makes an angle?
Formed by 2 rays with a common endpoint
Rays are called the sides of the angle
Common endpoint is called the vertex
Named by using 3 points on the angle, one point
on each side and the vertex, the point that
represents the vertex always has to be in the
middle or written second
Angle
A
side
vertex
B
ABC
C
side
Measure of an angle
You use a protractor to measure an angle –
different kinds different ways to do it
Angle measure is in degrees
Angle is always the shortest rotation between
the two sides about the vertex
Reflex measure is the largest rotation or the
angle subtracted from 360
Using a compass
2 different kinds in your boxes and some may
still have others
More Terms
Congruent Angles – have the same angle
measure, congruency markings
Angle Bisector – cuts an angle in half to have 2
congruent angles
These terms will be used a lot throughout the
year
Virtual Pool
Incoming Angle is the angle formed with the
path of the ball and the cushion (smaller of the
two angles)
Outgoing Angle is the angle formed by the
cushion and the path of the ball leaving ( smaller
angle)
Key idea here is the incoming angle and the
outgoing angle are congruent
Investigation
In your groups work on the Virtual Pool Math
problem
Answer the questions and work as a group
Widgets
Writing a good definition
What you are talking about / classify it / how it
differs from others(define it)
Ex A protractor is a geometric tool used to
measure angles
A square is ________ that ________
Counterexample
Find something that fits your definition but isn’t
really what you are trying to find
This is what I will do on purpose when you are
talking about a process or ideas to get a better
definition from you
A square is a figure with 4 congruent sides.
Draw a figure that fits this but is not a square
Investigation Defining Angles pg 49
Work through this investigation and as a group
come up with definitions
Right Angle
angle measure exactly 90 degrees
Acute Angle
angle measure is between 0 and 90
Obtuse Angle
angle measure is between 90 and 180
Con’t
Complementary Angles
2 angles that add to 90
Supplementary Angles
2 angles that add to 180
Vertical Angles
angles formed when two lines intersect, they are
across from each other and are congruent
Linear Pairs
2 angles that are adjacent and are supplementary
Adjacent – two angles that share a side and vertex
Homework
Pg 42
Pg 52
1,7-10, 16 and 17
15-24