Similar Polygons
Proving Similar Triangles
Similar Triangles
Scale Factor
100
In similar polygons all angles are congruent, and all sides are ______________.
What is: Proportional
100
In triangles, ABC and XYZ? Two corresponding angles are congruent in each. What is the reason they are similar?
What is AA similarity?
100
In triangles ABC X is between A and B, Y is between A and C, and Z is between B and C. AX = 4, AB = 12, AY = 6 and AC =18. Are Triangles ABC and AXY similar? What is the scale factor? Must show work.
What is YES? AX/AB = AY/AC? 4/12 = 6/18 = 1/3 <-- scale factor
100
On a map 1 inch = 50 miles. If point A is 7.5 inches from point B on the map. How far is point A from point B in the real world?
What is 375 miles?
200
ABCDE ~ FGHIJ. AB = 9, FG = 15, HI = 25. CD = ?
What is: 15
200
In triangles ABC and XYZ, AB = 9, BC = 12, AC = 15. XY = 15, YZ = 20, XZ = 25. Are the triangles similar? Write the similarity statement and reason.
What is ABC ~ XYZ by SSS similarity
200
In triangles ABC X is between A and B, Y is between A and C, and Z is between B and C. AX = 14, XB =7, AY = 20, YC =12. Are triangles ABC and AXY similar? Must show work.
What is NO? AX / AB = AY / AC? 14 / 21 = 20 / 31? NOPE.
200
On a map 2 inches = 80 miles. If Atlanta is 120 miles from Thimbleton in the real world, how far apart are they on the map?
What is 3 inches?
300
In, two polygons ABCD and EFGH: AB = 15, EF = 20, CD = 12 and GH = 18. Are the polygons similar?
What is: NO 15/20 = 3/4 but 12/18 = 2/3
300
In triangles ABC and XYZ, angle A = angle X, AB =10, XY = 24, AC = 5 and XZ = 12. Are the triangles similar, Write the similarity statement and reason.
What is ABC ~ XYZ by SAS similarity
300
In triangles ABC X is between A and B, Y is between A and C, and Z is between B and C. AX = 3 , XB = 1, and AY = 3YC Are triangles ABC and AXY similar? must show work.
What is YES? 3/1 =3YC/YC ; both = 3
300

A model car is 6 inches long, the real car is 15 feet long. What is the scale factor from the model to the real car (no unit conversions necessary)? 

What is 2.5?

400
ABCD ~ EFGH. AB = x-5, CD = 10, FG =15, BC = 10x. What is the length of AB?
What is: 4
400
In triangles, ABC and XYZ? angle A = angle Z and angle C = angle Y. What is the similarity statement of the triangles and reason?
What is ABC ~ ZXY by AA similarity
400
In triangles ABC X is between A and B, Y is between A and C, and Z is between B and C. Triangle ABC ~ AXY . AX = 9, XB = 12, AY =15 What is YC?
What is 20?
400

A model car is 6 inches long, the real car is 15 feet long. How many times longer is the real car than the model (unit conversions necessary)?

What is 30 times?

500
In polygons ABCD and EFGH, CD = 2x+4 , AB = 5x-2, EF = 1 and GH = 2. What is the length of CD?
What is: 6
500
In triangles ABC and XYZ, angle A = angle Z. AC = 50, AB =25, XZ =100 and XY =50. Are the triangles similar? If so, write the similarity statement and reason. If not, explain.
What is NO, They may not be similar because only one of the angles given is the included angle. It does not fit SAS similarity. Only if angle X = angle A then they are.
500
In triangles ABC X is between A and B, Y is between A and C, and Z is between B and C. AX = 7 , AY =4 and YC = 10. what is AB?
What is 24.5?
500

You are getting ready to move into a new house. The lengths of the walls of your room will be 10 feet by 12 feet. When you look at the blueprint, the lengths of the walls on the drawing are 7.5 inches by 9 inches. What is the scale used on the blueprint? (How many feet would one inch represent?)

What is 1 inch is 4/3 feet?

M
e
n
u