Transformations Flashcards
Describe what a translation does.
It slides a shape across and/or up/down.
What is a translation vector?
It’s stacked numbers inside huge brackets that tell you how far to move the shape.
What is the equation for a vertical line?
It’s always x= a number. For example: x=2 or x=0.
What is the equation for a flat horizontal line?
It’s always y= a number. For example: y=3 or y=5.
How do you fully describe a translation?
You need to say “This transformation is a translation” and also include:
- the translation vector
OR
- a description (like shift up 2 and left 5)
How do you fully describe a reflection?
You say, “This is a reflection through ____” and write down the equation for the line of reflection.
How do you fully describe a rotation?
You say, “This is a rotation.” And you have to provide:
- angle
- direction
- center of rotation
What are the steps to draw a rotation?
- Put a dot where the center of rotation is.
- Connect any corner of the shape to the dot.
- Make a big angle with that line you just drew (using a protractor).
- Trace your shape and the connecting line onto tracing paper.
- Stab the center of rotation and turn the tracing paper.
- Carefully copy the new shape onto your paper.
How do you draw a reflection?
- Draw the line of reflection.
- Count how far each corner is straight to the line, and then draw the new corner the same distance from the line on the other side. (This means that if the line is on a diagonal, you also have to count diagonally.)
How do you find the line of reflection?
- Pick two matching corners and make a dot exactly in the middle of them.
- Pick two other matching points and make a dot exactly in the middle of them.
- Connect your two new dots to make a big long line.
- Find the equation of the line using all of your math skills from Unit 4.
How to you find the center of rotation for a shape that is rotated 180°?
- Connect two corresponding corners with a line segment.
- Connect another two corresponding corners with a line segment.
- Make a dot at the intersection of your two line segments.
- Check answer with tracing paper.
How do you find the center of rotation for a 90° rotation?
- Trace the starting shape onto tracing paper.
- Guess and check different centers of rotation till you find it.
What is rotational symmetry?
It’s when a shape looks the same after turning it only part-way.
This picture has three orders of rotation.
What is reflection symmetry?
It’s how many ways you can fold a shape so that both sides of the fold line reflect each other.
What does enlargement mean?
To make something bigger.