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?
- No: AAA is needed, so all three angles must be given.
- Yes, by AAS.
- Yes, by ASA.
- No: all three pairs of sides 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 - Yes, by AAS.
- No: the side is not between the two angles.
- Yes, by ASA.
- No: AAA is needed, so all three angles must be given.
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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?
- No: the side is not between the two angles.
- Yes, by AAS.
- Yes, by ASA.
- 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.
- Yes, by ASA.
- No: all three pairs of sides must be given.
- No: AAA is needed, so all three angles must be given.
Use this
Two triangles, not to scale, with the given parts marked and labeled.
Tala checks two castle flags: m∠D = m∠V = 50°, m∠F = m∠S = 60° and m∠G = m∠U = 70°. Do these facts prove △DFG ≅ △VSU?
- Yes, by AAA: all three angles match.
- Yes, by ASA: two angles are enough.
- No: AAA gives the same shape, not always the same size.
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 AAA: the third angles match too.
- Yes, by AAS.
- No: the side is not between the two angles.
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 AAA: the third angles match too.
- Yes, by AAS.
Esme checks the two sides of a stepladder. ∠D = ∠U and DF = US are marked. Which one more fact proves △DFG ≅ △USV by ASA?
Two triangles, not to scale: △DFG and △USV, with ∠D and ∠U one arc, DF and US one tick. The matching table under them has ✓ on those two rows. Two triangles, not to scale: △DFG and △USV, with ∠D and ∠U one arc, DF and US one tick. The matching table under them has ✓ on those two rows. not to scale D F G U S V ∠D ∠U (check) DF US (check) - ∠F = ∠U
- ∠F = ∠S
- FG = SV
- ∠G = ∠V
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) - ∠C = ∠H
- ∠Q = ∠Y
- ∠Q = ∠H
- CQ = HY
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) - HS = CF
- ∠S = ∠U
- ∠H = ∠C
- ∠S = ∠F