This is circle theorems I am not rly good at this
1 answer:
Answer:
m∠BCD = 24°
Step-by-step explanation:
By the theorem,
"Angle subtended by an arc at the center of the circle is twice in measure of the angle subtended at the circumference."
m(∠BOD) = 2(m∠BFD)
= 2(78°)
= 156°
Therefore, m(arc BD) = m∠BOD = 156°
Since, m(arc BD) + m(arc BFD) = 360°
156° + m(arc BFD) = 360°
m(arc BFD) = 360 - 156
= 204°
Since, "angle formed outside the circle by the intersection of two tangents measure half of the difference of the intercepted arcs".
m∠BCD =
=
= 24°
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