http://www.ck12.org Chapter 7. Similarity
Guided Practice
Find the missing variables:
Answers:
- Set up a proportion and solve.
20
8
=
25
y
20 y= 200
y= 10
- Set up a proportion and solve.
20
y
=
15
28 −y
15 y= 20 ( 28 −y)
15 y= 560 − 20 y
35 y= 560
y= 16
- Set up a proportion and solve.
12
z
=
15
9 −z
15 z= 12 ( 9 −z)
15 z= 108 = 12 z
27 z= 108
z= 4
Practice
Find the value of the missing variable(s).
1.
2.
Find the value of each variable in the pictures below.