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Aptitude · Q221

Geometry

Competitive Exams · Aptitude · question 221

Q221

In equilateral ΔABC, D and E are points on the side AB and AC, respectively, such that AD = CE. BE and CD intersect at F. The measure (in degrees) of ∠CFB is :

A.
120°
Answer
B.
125°
C.
135°
D.
105°

Answer: Option A

Solution

Answer: Option A
Solution:
Geometry mcq question image
ΔADC and ΔEBC
AD = EC
∠A = ∠C = 60°
AC = BC
ΔADC ∽ ΔEBC   [By SAS]
Let ∠ECF = ∠EBC = x
∠FCB = 60° - x
In ΔBFC
∠B + ∠C + ∠F = 180°
x + 60° - x + ∠BFC = 180°
∠BFC = 180° - 60° = 120°
∠CFB = 120°