Triangle congruence: ASA and AAS
Grade 10 Math Worksheet

Circle the best answer.
Milo checks two kite halves: m∠D = m∠S = 48°, DF = SU = 9 cm and m∠F = m∠U = 70°. Which is true about △DFG and △SUV?
- Yes, by ASA.
- No: all three pairs of sides must be given.
- Yes, by AAS.
- No: AAA is needed, so all three angles must be given.
Noah checks two tent flaps: m∠C = m∠W = 41°, m∠H = m∠Y = 83° and HQ = YS = 12 cm. Which is true about △CHQ and △WYS?
Two triangles, not to scale, with the given parts marked and labeled. The matching table for △CHQ ≅ △WYS has ✓ on the three given rows. Two triangles, not to scale, with the given parts marked and labeled. The matching table for △CHQ ≅ △WYS has ✓ on the three given rows. not to scale C H Q 41 deg 83 deg 12 cm W Y S 41 deg 83 deg 12 cm triangle CHQ triangle WYS check C W check H Y check HQ YS check - No: the side is not between the two angles.
- No: AAA is needed, so all three angles must be given.
- Yes, by ASA.
- Yes, by AAS.
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Two triangles, not to scale, with the given parts marked and labeled. The matching table for △GUW ≅ △DFH has ✓ on the three given rows.
Pia checks two boat sails: m∠U = m∠F = 57°, m∠W = m∠H = 66° and GU = DF = 15 cm. Which is true about △GUW and △DFH?
- Yes, by AAS.
- Yes, by ASA.
- No: the side is not between the two angles.
- No: AAA is needed, so all three angles must be given.
Ren checks two rug triangles: m∠S = m∠V = 38°, SY = VG = 11 cm and m∠Y = m∠G = 104°. Which is true about △QSY and △CVG?
Two triangles, not to scale, with the given parts marked and labeled. The matching table for △QSY ≅ △CVG has ✓ on the three given rows. Two triangles, not to scale, with the given parts marked and labeled. The matching table for △QSY ≅ △CVG has ✓ on the three given rows. not to scale 38 deg 104 deg 11 cm 38 deg 104 deg 11 cm S Y Q V G C triangle QSY triangle CVG (check) mangle S mangle V (check) SY VG (check) - Yes, by AAS.
- No: all three pairs of sides must be given.
- No: AAA is needed, so all three angles must be given.
- Yes, by ASA.
Use this
Two triangles, not to scale, with the given parts marked and labeled.
Zee checks two quilt patches: m∠C = m∠S = 44°, m∠H = m∠Y = 75° and CW = SQ = 10 cm. Do these facts prove △CHW ≅ △SYQ?
- Yes, by AAS.
- Yes, by AAA: the third angles match too.
- No: the side is not between the two angles.
Ari checks two window panes: m∠G = m∠H = 35°, m∠S = m∠Q = 65° and m∠U = m∠D = 80°. Do these facts prove △GSU ≅ △HQD?
- Yes, by ASA: two angles are enough.
- No: AAA gives the same shape, not always the same size.
- Yes, by AAA: all three angles match.
Bo checks two sandwich halves: m∠V = m∠W = 53°, m∠Y = m∠C = 68° and QV = FW = 14 cm. Do these facts prove △QVY ≅ △FWC?
- No: the side is not between the two angles.
- Yes, by AAS.
- Yes, by AAA: the third angles match too.
Use this
Two triangles, not to scale: triangle CQW and triangle HYD, with ∠W and ∠D one arc, QW and YD one tick. The matching table under them has (check) on those two rows.
Jun checks two bike-frame triangles. ∠W = ∠D and QW = YD are marked. Which one more fact proves △CQW ≅ △HYD by ASA?
Two triangles, not to scale: △CQW and △HYD, with ∠W and ∠D one arc, QW and YD one tick. The matching table under them has ✓ on those two rows. Two triangles, not to scale: △CQW and △HYD, with ∠W and ∠D one arc, QW and YD one tick. The matching table under them has ✓ on those two rows. C Q W H Y D ∠W = ∠D (check) QW = YD (check) - ∠Q = ∠H
- ∠C = ∠H
- CQ = HY
- ∠Q = ∠Y
Kira checks two paper triangles. ∠G = ∠U and GS = UF are marked. Which one more fact proves △GHS ≅ △UCF by ASA?
Two triangles, not to scale: △GHS and △UCF, with ∠G and ∠U one arc, GS and UF one tick. The matching table under them has ✓ on those two rows. Two triangles, not to scale: △GHS and △UCF, with ∠G and ∠U one arc, GS and UF one tick. The matching table under them has ✓ on those two rows. not to scale G H S U C F ∠G ∠U (check) GS UF (check) - ∠S = ∠U
- ∠H = ∠C
- HS = CF
- ∠S = ∠F
“not to scale” Luz checks two park shapes on a map. ∠Y = ∠C and UY = QC are marked. Which one more fact proves △UVY ≅ △QSC by ASA?
Two triangles, not to scale: △UVY and △QSC, with ∠Y and ∠C one arc, UY and QC one tick. The matching table under them has ✓ on those two rows. Two triangles, not to scale: △UVY and △QSC, with ∠Y and ∠C one arc, UY and QC one tick. The matching table under them has ✓ on those two rows. U V Y Q S C ∠Y = ∠C (check) UY = QC (check) - ∠U = ∠Q
- UV = QS
- ∠U = ∠C
- ∠V = ∠S