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?
△CHQ with ∠C, ∠H and side HQ marked; △YWS with ∠S labeled (5x + 2)°. Noah checks two kite halves. △CHQ ≅ △YWS by AAS, with m∠C = 39° and m∠H = 84°. In △YWS, m∠S = (5x + 2)°. What is x?
“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: equal angles alone prove only the same shape (AAA).
- Yes, by ASA.
- No: the triangles point in different directions.
- No: only one pair of sides is marked.
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: only one pair of sides is marked.
- No: equal angles alone prove only the same shape (AAA).
- Yes, by AAS.
- No: the triangles point in different directions.
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. - No: the triangles point in different directions.
- Yes, by ASA.
- Yes, by AAS.
- 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. - No: no pair of sides is marked.
- Yes, by AAS.
- 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 ≅ △WSC by ASA
- △DFG ≅ △WCS by ASA
- △DFG ≅ △WCS by AAS
- △DFG ≅ △CSW 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 ≅ △YSD by AAS
- △CHU ≅ △YDS by ASA
- △CHU ≅ △YDS by AAS
- △CHU ≅ △DSY by AAS
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Two triangles, not to scale: triangle HVY on the left and triangle QGD on the right, turned. Marks: ∠V and ∠G one arc; VY and GD one tick; ∠Y and ∠D two arcs. The matching table under them is blank.
Luz checks two park shapes on a map. The marks show which parts are equal. Which statement and rule are right?
Two triangles, not to scale: △HVY on the left and △QGD on the right, turned. Marks: ∠V and ∠G one arc; VY and GD one tick; ∠Y and ∠D two arcs. The matching table under them is blank. Two triangles, not to scale: △HVY on the left and △QGD on the right, turned. Marks: ∠V and ∠G one arc; VY and GD one tick; ∠Y and ∠D two arcs. The matching table under them is blank. H V Y Q G D - △HVY ≅ △QDG by ASA
- △HVY ≅ △QGD by ASA
- △HVY ≅ △QGD by AAS
- △HVY ≅ △DGQ by ASA

