This math topic focuses on solving problems related to inscribed triangles in circles, where one side of the triangle is a diameter. Specifically, it involves finding the missing angle of the triangle using properties from circle geometry. Each question presents a triangle with one known angle and requires calculating the second angle, exploiting the theorem that an angle inscribed in a semicircle is a right angle (90 degrees). The topic is suitable for learners at an intermediate level in geometry.
Work on practice problems directly here, or download the printable pdf worksheet to practice offline.
Practice:
Inscribed Triangle on Diameter - Missing Angle
Complete these online problems with 80% or 4 correct answers in a row. Results are immediate.
Find angle MCD in degrees given that MDC is 25º and CD forms a diameter
Geometry of Circles - Inscribed Triangle on Diameter - Missing Angle Worksheet
| Math worksheet on 'Geometry of Circles - Inscribed Triangle on Diameter - Missing Angle (Level 2)'. Part of a broader unit on 'Geometry - Intermediate - Intro' Learn online: app.mobius.academy/math/units/geometry_intermediate_intro/ |
| Find angle RYX in degrees given that RXY is 25º and YX forms a diameter |
| 80º |
| 125º |
| 5º |
| 20º |
| 140º |
| 65º |
| Find angle CPR in degrees given that CRP is 45º and PR forms a diameter |
| 15º |
| 90º |
| 60º |
| 120º |
| 0º |
| 45º |
| Find angle ZRP in degrees given that ZPR is 25º and RP forms a diameter |
| 110º |
| 65º |
| 95º |
| 50º |
| 20º |
| 80º |
| Find angle PZR in degrees given that PRZ is 45º and ZR forms a diameter |
| 30º |
| 0º |
| 15º |
| 75º |
| 45º |
| 135º |
| Find angle MBN in degrees given that MNB is 65º and BN forms a diameter |
| 50º |
| 85º |
| 20º |
| 25º |
| 55º |
| 115º |
| Find angle RCX in degrees given that RXC is 65º and CX forms a diameter |
| 35º |
| 70º |
| 55º |
| 115º |
| 20º |
| 25º |
| Find angle YBX in degrees given that YXB is 35º and BX forms a diameter |
| 20º |
| 40º |
| 130º |
| 100º |
| 55º |
| 25º |