Dilations
Similarity
Slope
Dilations pt. 2
100
True or False? Dilations always make a figure smaller.
What is False?
100
These two things must be true about similar figures
What are
1) corresponding sides (proportional)
2) corresponding angles (equal)
100
Slope is the change in ______ over _____.
What is rise over run?
Vertical distance (Y) over Horizontal distance (X)
What is rise over run?
Vertical distance (Y) over Horizontal distance (X)
100
True/False
Dilations increase the measure of angles.
False
200
A dilation might change the size of a figure's side lengths but never the _______.
What are angles?
200
Any one or more of these moves can be used to prove similarity. (list at least two moves)
What are
1) Translations
2) Rotations
3) Reflections
4) Dilations
200
If a triangle has a horizontal distance of 5 and a vertical distance of 3, what is it's slope?
What is 3/5?
200
True/False
Dilations ALWAYS increase the length of line segments or figures.
What is FALSE.
Explain why!
300
Dilations always produce ___________ figures.
What is similar?
300
True/False
Triangle D has 90 degree, 30 degree, and 60 degree angles. Triangle E has all 60 degree angles. They are similar.
What is FALSE?
Explain why!
300
The slope of this line.
What is 2/3?
300
You have two similar triangles. Triangle MNK has the following side lengths: MN = 2 units, NK = 5 units and MK = 3 units. Triangle MNK has been dilated to get Triangle M’N’K’. If you know that the length of M’N’ = 10 units, then the lengths of N’K’ and M’K’ are ______ and _______.
What are 25 and 15?
400
What two things do we need when describing dilations?
What are
1) Center Point of Dilation
2) Scale Factor
400
True or false: Similar figures are always congruent.
False. Similar figures are sometimes congruent
400
If a triangle has a vertical distance of 2 and a horizontal distance of 4, what is the slope?
What is 2/4?
400
If a figure has coordinates S (-4, -2), T (-3, 1) and U (-2, -2), what would the new coordinates be if it was dilated by 3, with (0,0) being the center of dilation?
What is S’ (-12, -6), T’ (-9, 3), and U’ (-6, -6)?
500
How will dilating a figure with a scale factor of 1/3 change a figure?
What is it will make the figure 3 times smaller from the center of dilation (or reduced/smaller figure)?
500
Dilations can result in a congruent and similar figure if their scale factor is this number.
What is 1?
500
The slope of a line is a number we can calculate using at least ____ points on the line?
What is 2?
500
If a figure has coordinates A (-6, -12), B (-4, 4) and C (-6, -10), what would be the new coordinates of C if the figure was dilated by 1/2?
What is (-3, -5)?