Transformations Flashcards
What does the bottom number of a vector represent?
How far the object is moved up or down
How do I recognise
a rotation?
The object has been spun around
Describe the line
x = -7
Vertical line,
going through -7 on the x axis
What is required to describe
a translation?
Translation
A vector
Why don’t you need a direction for a 180 degree rotation?
The image lands in the same place either clockwise or anti-clockwise
Describe the line
y = 5
Horizontal line,
going through 5 on the y axis
How far round is 270 degrees?
3/4 turn
Describe the line
x = 4
Vertical line,
going through 4 on the x axis
Where is the origin?
(0, 0)
At the centre of the grid
Describe the line
y = x
Diagonal line.
Positive gradient (upward),
going through the origin
What is an invariant point?
A coordinate that has not changed after the transformation has happened
What is the equation of a diagonal line,
going through the origin,
with a positive gradient of 1?
y = x
What does the top number of a vector represent?
How far the object is moved left or right
What type of scale factor rotates an object as well as changing its size?
A negative scale factor
Describe the line
y = -x
Diagonal line.
Negative gradient (downward),
going through the origin
How do you reflect an object?
Draw the mirror line.
Count the number of squares directly to the mirror line.
(perpendicular)
Count the same number of squares on the other side of the mirror line.
Repeat for each corner
How do you enlarge an object?
From the centre count the squares to the first corner.
Multiply this by the scale factor.
From the centre count the new amount of squares to the corner of the image.
Repeat for each corner
How do I recognise
a reflection?
The object has been flipped over
How do you find the centre of enlargement?
Draw ‘ray’ lines from corresponding corners of the object and the image.
Where they cross is the centre of enlargement
What is the equation of the line that is:
Parallel to the y axis and going through 1 on the x axis?
x = 1
Have far round is 90 degrees?
1/4 turn
How do you translate an object?
Put a dot on a corner of the object.
Move the dot left/right by the number on the top of the vector.
Move the dot up/down by the number on the bottom of the vector.
Draw the image at this point
What type of scale factor makes an object go smaller?
A fractional scale factor
What is required to describe
an enlargement?
Enlargement
Scale factor
Centre of enlargement
What is required to describe
a reflection?
Reflection
The mirror line
Describe the line
y = 3
Horizontal line,
going through 3 on the y axis
What is the equation of a diagonal line,
going through the origin,
with a negative gradient of 1?
y = -x
What is the equation of the line that is:
Parallel to the x axis and going through 1 on the y axis?
y = 1
What does a fractional scale factor do to an object?
Makes it smaller
How do you find the centre of rotation?
Draw the object on some tracing paper.
Guess where the centre is and with your pencil on this point spin the paper.
If it lands on the image you have found the centre.
If not try a different point
How do I recognise
an enlargement?
The object has changed size,
either smaller or bigger
How do you rotate an object?
Mark the centre.
Draw the object on the tracing paper.
Put your pencil on the centre and spin the paper in the direction for the correct angle of turn.
Draw the image at this place
How do I recognise
a translation?
The object has slide along,
left/right, up/down
What does a negative scale factor do to an object?
Rotates the object
and
changes it size
Describe the line
x = 6
Vertical line,
going through 6 on the x axis
Describe the line
y = -2
Horizontal line,
going through -2 on the y axis
What is required to describe
a rotation?
Rotation
Angle of turn and direction
Centre of rotation
