#Solving for angles in diagram involving circles and triangles
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(2) is solvable but (1) is unsolvable
!nosols, please.
As a helper, please do not give out answers that could be copied as a homework solution. Have the student work through the problem themselves and guide them along the way.
i can also give full explanation or just let you solve it by giving hints
we will use this diagram to solve the question
∠CAB = 2∠CDB { angle subtended by chord at the centre of the circle is twice the angle subtended by chord at circumference of the circle.}
angle is subtended by chord CB
∠CAB = 71
∠ACB = ∠ABC {Angles opp to equal sides}
As, AC = AB {equal radii}
∠ABC + ∠ACB + ∠CAB = 180 {Angle sum property of triangle}
2∠ABC + 71 = 180
2∠ABC = 109
∠ABC = 109/2 = 54.5
Solving for angles in diagram involving circles and triangles
Now,
∠DAE = ∠FAB
∠FAB = 55
Now, ∠AFB = ∠ABF {Angles opp to equal sides} ---(1)
As, AF = AB {equal radii}
so we can get,
∠AFB + ∠ABF + ∠ FAB = 180
From this we get.
2∠AFB + 55 = 180
2∠AFB = 125
∠AFB = 62.5
so , ∠ABF = 62.5
∠ABF = ∠FBC + ∠ ABC
putting values of angles we get
62.5 = a + 54.5
a = 8
∠AFB = 62.5 so ∠b = 62.5
by this theorem
(2) Hence, a = 8 and b = 62.5