8.3

Question 1

Similarity two defs

Answer 1

Similar triangles are triangles which have the same shape but not the same size.
Similar triangles are those which have equal corresponding angles and proportional corresponding sides.

Question 2

1st general statement

Answer 2

Draw triangles and label ABC(smaller) and XYZ(larger)
If A=X B=Y C=Z / |AB| |BC| |AC|
——=—-=——
|XY| |YZ| |XZ| ,
then ‘triangle shape’ABC ~ ‘triangle shape’XYZ

Question 3

1st test statement

Answer 3

If two triangles have two pairs of equal corresponding angles, then these triangles are the similar.

Question 4

1st test

Answer 4

Drawings with two angles marked and whole thing labelled

If A=X
B=Y ,
then ‘triangle shape’ABC~‘triangle shape’XYZ.

Question 5

2nd test statement

Answer 5

If two triangles have three pairs of proportional corresponding sides, then these triangles are similar.

Question 6

2nd test

Answer 6

Drawings with nothing labelled apart from letters

If 
 |AB| |BC| |AC| 
 ——=—-=—— ,
 |XY| |YZ| |XZ|  
then ‘triangle shape’ABC~‘triangle shape’XYZ.

Question 7

Third test statement

Answer 7

If two triangles have one pair of equal corresponding angles and two pairs of proportional corresponding angles, then these triangles are similar.

Question 8

Third test

Answer 8

Drawings with one angle labelled and letters

If 
A=X
|AB|   |AC| 
 ——=—— ,
|XY|   |XZ|  
then ‘triangle shape’ABC~‘triangle shape’XYZ

Question 9

What do I need for each test

Answer 9

An example with proof
Drawing with whatever needed labelled
Statements with values substituted in