Dihlations
Similar Polygons
Similar triangles, postulate applications
Triangle proofs and properties
100
The image is enlarged if the scale factor is
Greater than 1
100
True or False: All congruent polygons are similar
True
100
In two similar triangles, the ratio of the lengths of corresponding sides is 5/3. If the area of the smaller triangle is 27 square units, what is the area of the larger triangle.
75
100
What is always the first reason?
The given
200
A triangle ABC is dilated with a scale factor of 2. What is true regarding the corresponding angles in the dilated triangle?
The corresponding angles remain the same.
200
Are these two rectangles similar?
what is no
200
Lance the alien is 5 feet all. His shadow is 8 feet long. At the same time of day, a tree's shadow is 32 feet long. What is the height of the tree?
a) 20
200
What property states that any geometric figure is congruent to itself?
Reflexive property
300
Find the scale factor if the radius of the original circle changes from 8 units to 2 units after dilation.
what is 1/4
300
Suppose △ABC∼△JKL. Based on the similarity statement, which angles are congruent and which sides are proportional?
∠A≅∠J,∠B≅∠K, and ∠C≅∠L. The sides in a proportion: AB/JK=BC/KL=AC/JL. Note that the proportion could be written in different ways. For example, AB/BC=JK/KL is also true.
300
The angle of the roof on Kaya’s dollhouse is 56 degrees. She built a scale model of the dollhouse with a scale
ratio of 1 : 4. What is the measure of the angle of the roof of the model?
56 degrees
300
What property states that if two objects are congruent to each other you can replace one with the other in a statement and the value wouldn't change?
Substitution
400
The ratio of the corresponding sides of dilated figure and the original figure, when the scale factor is k, is
k:1
400
True or False: All similar polygons are congruent.
False. Similarity only requires shape, while all congruent polygons are similar, they are not all the same size.
400
A six-foot-tall person is standing next to a flagpole. The person is casting a shadow 1 ½ feet in length, while the flagpole is casting a shadow 5 feet in length. How tall is the flagpole?
20 feet
400
What exactly are you proving when using similar triangles to prove the Pythagorean theorem?
You are proving that the relationship a² + b² = c² holds true for all right triangles, where 'a' and 'b' are the lengths of the legs and 'c' is the length of the hypotenuse
500
Given
A(−5,−9)
and
A′(−45,−81),
find the scale factor. Assume the center of dilation is the origin.
k=9
500
What are the values of x and y?
x=15 and y=25
500
If
AB/PQ=BC/QR=AC/PR
, then
500
What do you use CPCTC for in a proof?
to prove the additional sides or angles are congruent