Dialations Notes
January 26, 2015
Dila on - transforma on that produces an image
that is the _________________ as the original but
_______________________.
A dila on is _____________ to the original figure.
Dila ons are centered around the origin (0, 0), unless
otherwise stated.
Scale factor – is
, which is a ___________.
If the scale factor is ______________________,
the figure becomes _______________.
If the scale factor is ______________________,
the figure becomes __________________.
Rule:
where f represents the scale factor.
Example 1: If the scale factor is 3, how would
you write the rule?
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Dialations Notes
January 26, 2015
Example 2:
Triangle ABC has ver ces A (0, 2), B (4, 4), and C (-1, 4).
What are the ver ces of its image with a scale factor of 4?
Example 3:
Quadrilateral PQRS has ver ces P (-2, 4), Q (4, 4), R (4, -2),
and S (- 4, - 4). It is dilated by a scale factor of ½.
a) What are the coordinates of the image? Graph them.
6
y
5
4
3
2
1
x
-6
-5
-4
-3
-2
-1
0
-1
1
2
3
4
5
6
-2
-3
-4
-5
-6
b) Demonstrate these quadrilaterals are similar by
comparing the ra os of the lengths.
c) What do you no ce about the angle measurements of the
two figures?
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Dialations Notes
January 26, 2015
Example 4:
If the scale factor is
, how would you write the general
rule? Is this an enlargement or a reduc on?
Example 5:
Quadrilateral A’B’C’D’ is a dila on of quadrilateral ABCD.
Find the scale factor. Classify the dila on as an
enlargement or a reduc on.
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Dialations Notes
January 26, 2015
Example 6:
Triangle XYZ is graphed below. Draw and label
Triangle X’Y’Z’ a1er a dila on using a scale factor of
two.
What will be the coordinates of point Y” a1er a reflec on
of polygon X’Y’Z’ over the x-axis?
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Dialations Notes
January 26, 2015
For each problem, there is a composition of motions.
Using your algebraic rules, come up with a new rule
after both transformations have taken place.
1) Translate the triangle 3 units le1 and 2 units up,
and then reflect the triangle over the line y=-x.
2) Rotate the triangle 180 degrees clockwise, and
then dilate the figure by a scale factor of 1/3.
3)Translate the triangle 5 units right and 3 units
down, and then reflect the triangle over the x-axis
and dilate by a scale factor of 2.
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Dialations Notes
January 26, 2015
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