1. similar triangles

2. Two triangles are called “similar”
if their corresponding angles have
the same measure.      

3. a A b B c C Two triangles are called “similar”
if their corresponding angles have
the same measure. 
Ratios of corresponding
sides are equal. C A  a c     b B a A b B c C = =

4. application

5. Mary is 5 ft 6 inches tall.
She casts a 2 foot shadow.
The tree casts a 7 foot shadow.
How tall is the tree?

6. Mary is 5 ft 6 inches tall.
She casts a 2 foot shadow.
The tree casts a 7 foot shadow.
How tall is the tree?
Mary’s height
Tree’s height
Mary’s shadow
Tree’s shadow = x
5.5 2 7

7. Mary is 5 ft 6 inches tall.
She casts a 2 foot shadow.
The tree casts a 7 foot shadow.
How tall is the tree?
5.5 x 2 7 =
Mary’s height
Tree’s height
Mary’s shadow
Tree’s shadow = x
5.5 2 7

8. 5.5 x 2 7 =
7 ( 5.5 ) = 2 x
= 2 x
x =
The height of the tree is feet