Triangle congruence: ASA and AAS
Grade 10 Math Worksheet - Challenge Me

Circle the best answer, or write your answer on the line.
Two triangles, not to scale. Milo checks two tent flaps. △DFG ≅ △SUV by AAS, with m∠D = 48° and m∠F = 67°. In △SUV, m∠V = (3x + 5)°. What is x?
Pia checks two boat sails. △GUW ≅ △FHD by AAS, with m∠G = 71° and m∠U = 45°. In △FHD, m∠D = (4x + 4)°. What is x?
Two triangles, not to scale: △GUW with ∠G, ∠U and side UW marked; △FHD with ∠D labeled (4x + 4)°. Two triangles, not to scale: △GUW with ∠G, ∠U and side UW marked; △FHD with ∠D labeled (4x + 4)°. G U W H D F (4x + 4)° “Two triangles, not to scale:” Ren checks two castle flags. △QVY ≅ △CGS by AAS, with m∠Q = 26° and m∠V = 92°. In △CGS, m∠S = (2x + 4)°. What is x?
Two triangles, not to scale: △QVY with ∠Q, ∠V and side VY marked; △CGS with ∠S labeled (2x + 4)°. Two triangles, not to scale: △QVY with ∠Q, ∠V and side VY marked; △CGS with ∠S labeled (2x + 4)°. Q V Y C G S (2x + 4)° Tala checks two bike-frame triangles. Only DF ∥ SU and DC = UC are marked. Is △DCF ≅ △UCS, and by which rule?
Segments DU and FS cross at C, not to scale; DF and SU drawn, with arrows showing DF ∥ SU. DC and UC one tick. Segments DU and FS cross at C, not to scale; DF and SU drawn, with arrows showing DF ∥ SU. DC and UC one tick. D U F S C Not to scale. - No: the triangles point in different directions.
- Yes, by ASA.
- No: only one pair of sides is marked.
- No: equal angles alone prove only the same shape (AAA).
Zee checks the two sides of a stepladder. Only DF ∥ SU and FC = SC are marked. Is △DCF ≅ △UCS, and by which rule?
Segments DU and FS cross at C, not to scale; DF and SU drawn, with arrows showing DF ∥ SU. FC and SC two ticks. Segments DU and FS cross at C, not to scale; DF and SU drawn, with arrows showing DF ∥ SU. FC and SC two ticks. D U F S C Not to scale. - No: the triangles point in different directions.
- No: only one pair of sides is marked.
- Yes, by AAS.
- No: equal angles alone prove only the same shape (AAA).
Ari checks two kite halves. Only ∠HQG = ∠WQG and ∠HGQ = ∠WGQ are marked. Is △HQG ≅ △WQG, and by which rule?
Segment QG, not to scale, with H above it and W below it; QH, HG, QW and WG drawn. ∠HQG and ∠WQG one arc; ∠HGQ and ∠WGQ two arcs. Segment QG, not to scale, with H above it and W below it; QH, HG, QW and WG drawn. ∠HQG and ∠WQG one arc; ∠HGQ and ∠WGQ two arcs. Q G H W Not to scale. - Yes, by ASA.
- Yes, by AAS.
- No: the triangles point in different directions.
- No: no pair of sides is marked.
Bo checks two sandwich halves. Only ∠QHG = ∠QWG and ∠HQG = ∠WQG are marked. Is △HQG ≅ △WQG, and by which rule?
Segment QG, not to scale, with H above it and W below it; QH, HG, QW and WG drawn. ∠QHG and ∠QWG one arc; ∠HQG and ∠WQG two arcs. Segment QG, not to scale, with H above it and W below it; QH, HG, QW and WG drawn. ∠QHG and ∠QWG one arc; ∠HQG and ∠WQG two arcs. Q G H W Not to scale. - Yes, by AAS.
- No: no pair of sides is marked.
- Yes, by ASA.
- No: the triangles point in different directions.
Esme checks two window panes. The marks show which parts are equal. Which statement and rule are right?
Two triangles, not to scale: △DFG on the left and △WCS on the right, turned. Marks: ∠D and ∠W one arc; DF and WC one tick; ∠F and ∠C two arcs. The matching table under them is blank. Two triangles, not to scale: △DFG on the left and △WCS on the right, turned. Marks: ∠D and ∠W one arc; DF and WC one tick; ∠F and ∠C two arcs. The matching table under them is blank. Two triangles, not to scale D F G W C S matching table - △DFG ≅ △CSW by ASA
- △DFG ≅ △WCS by ASA
- △DFG ≅ △WCS by AAS
- △DFG ≅ △WSC by ASA
“not to scale” Jun checks two quilt patches. The marks show which parts are equal. Which statement and rule are right?
Two triangles, not to scale: △CHU on the left and △YDS on the right, turned. Marks: ∠C and ∠Y one arc; ∠H and ∠D two arcs; HU and DS one tick. The matching table under them is blank. Two triangles, not to scale: △CHU on the left and △YDS on the right, turned. Marks: ∠C and ∠Y one arc; ∠H and ∠D two arcs; HU and DS one tick. The matching table under them is blank. C H U Y D S - △CHU ≅ △DSY by AAS
- △CHU ≅ △YDS by AAS
- △CHU ≅ △YDS by ASA
- △CHU ≅ △YSD by AAS
Read this first
Use this
Two triangles, not to scale: triangle GQS on the left and triangle VUF on the right, turned. Marks: ∠Q and ∠U one arc; ∠S and ∠F two arcs; GQ and VU one tick. The matching table under them is blank.
Kira checks two rug triangles. The marks show which parts are equal. Which statement and rule are right?
Two triangles, not to scale: △GQS on the left and △VUF on the right, turned. Marks: ∠Q and ∠U one arc; ∠S and ∠F two arcs; GQ and VU one tick. The matching table under them is blank. Two triangles, not to scale: △GQS on the left and △VUF on the right, turned. Marks: ∠Q and ∠U one arc; ∠S and ∠F two arcs; GQ and VU one tick. The matching table under them is blank. triangle GQS triangle VUF G Q S V U F - △GQS ≅ △FUV by AAS
- △GQS ≅ △VUF by AAS
- △GQS ≅ △VFU by AAS
- △GQS ≅ △VUF by ASA