Download 4.1 Congruent Figures - Cardinal O'Hara High School

4.1 Congruent Figures
• Congruent figures have the same size and shape.
– When two figures are congruent, you can slide, flip, or
turn one so that it fits exactly on the other one.
Congruent Figures
• Congruent Polygons have congruent corresponding
parts – their matching sides and angles. When you
name congruent polygons, you must list
corresponding vertices in the same order.
Finding Congruent Parts
• If HIJK LMNO, what are the congruent
corresponding parts?
HI  LM
IJ  MN
JK  NO
KH  OL
H  L
I  M
J  N
K  O
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.
Examples 3 and 4
• See textbook p. 220 – 221 for the two
examples.
More Practice!!!!!
• Homework – Textbook p. 222 # 8 – 31.