1.1 Transformations, Orientation, and Congruence
Name the 3 Transformations!
Translations, Reflections, Rotations
Can you name the two words that can help us remember the transformations? Translation means ___ and reflection means ___.
TranSLation is to SLide
ReFLection is to FLip
What is the definition of vertical angles?
Opposite angles that share the same vertex formed by a pair of intersecting lines.
( x +- a, y +- b)
Which transformation does NOT maintain congruence?
Dilation
What is the definitions of preserving congruence?
To preserve congruence means that the shape and size remains the same AFTER the transformation is done.
What do the pre-image coordinates of (2,2) turn into when translated 4 to the right and 3 down? Tell me the image coordinates.
(2,2) -> (6, -1)
What is the definition of a transversal?
A line that cuts through parallel lines.
What coordinate is affected when translation left and right?
THE X-COORDINATE!
What types of angles do perpendicular lines create?
Right angles
What is the definition of preserving orientation?
To preserve orientation means the shape will be facing the same directions AFTER the transformation is complete.
What is the algebraic representation for a reflection over the x-axis?
(x , y) -> (x , -y)
Show me a pair of intersection lines with your arms.
Arms should cross!
What coordinate is affected when translation up and down?
THE Y-COORDINATE!
What do we call two angles whose sum is 180 degrees?
Supplementary Angles
Which transformations preserve BOTH congruence and orientation?
ONLY TRANSLATION
What is the algebraic representation for a reflection over the y-axis?
(x , y) -> (-x , y)
Show me a pair of parallel lines.
Arms should not cross.
How many days are there until Halloween?
22 days!
True or False
Corresponding angles are congruent.
TRUE
What is the name of the ' in A'?
PRIME NOTATION
What word does Mrs. Graves like to use other than negative when referring to coordinates changing signs and why?
OPPOSITE BECAUSE A NUMBER THAT IS ALREADY NEGATIVE TURNS THE OPPOSITE SIGN!!
When you have vertical angles or angles cut by a transversal, what happens to the angle measures?
They are congruent.
How many days are left until Winter Break?
73 days!
What are complementary angles?
Two angles whose measures add up to 90 degrees.