Download 4-1: Congruent Figures

4-1: Congruent Figures
Congruent Figures
 Congruent Polygons
 Have congruent corresponding parts
 Must list corresponding vertices in the same
order when naming.
Congruence Statement
ABCD  EFGH
B
F
A
D
E
C
G
H
AB  EF
BC  FG
CD  GH
AD  EH
A  E
C  G
B  F
D  H
Complete Got It? #1 p. 219
Using Congruent Parts
The sides of a roof suggest congruent triangles FJG  HIE .
What is the measure of m1?
90  48  mGFJ  180
F
138  mGFJ  180
mGFJ  42
42
H
1
48
G
J
mGFJ  m1
42  m1
Complete Got It? #2 p. 219
mV  83
I
E
Theorem 4-1: Third Angles Theorem
 If two angles of one triangle are congruent to
two angles of another triangle, then the third
angles are congruent.
If…
Then…
C  F
A  D and B  E
D
A
B
C E
F
Homework: p.222 #’s, 18-24, 35-39