Teach Genie
Teach it back in your own words, spot gaps, and remember it better.
Congruent triangles are exactly the same shape and exactly the same size. One triangle can be moved, rotated, or reflected onto the other, but every matching side and angle still agrees.
When we write △ABC≅△DEF\triangle ABC \cong \triangle DEF△ABC≅△DEF, the order tells you the matching vertices: A↔DA \leftrightarrow DA↔D, B↔EB \leftrightarrow EB↔E, and C↔FC \leftrightarrow FC↔F. Getting this order right matters because it tells you which angles and sides correspond.
Question 1
4 marksPQRS PQRS\,PQRS is a kite where PQ=PSPQ = PSPQ=PS and QR=SRQR = SRQR=SR.
After proving two triangles are congruent, what equality fact can you use?
Revision notes for WJEC GCSE Maths Congruent Triangles: explanations and worked examples.
1 of 5
A diagonal ACACAC divides parallelogram ABCDABCDABCD into triangles ABCABCABC and CDACDACDA. Which congruence test proves that the triangles are congruent?