Question

In the given figure, ∠BAC = 70°, ∠ACB = 45° and ∠DEA = 140°. What is the value of ∠BDE?

• A. 10
• B. 15
• C. 20
• D. 25

Answer 1

Answer:

D. 25

Sum of angles of a triangle is 180 ∠ABC + 70 + 45 = 180 ∠ABC = 65 ∠DBE = 180 - ∠ABC = 180 - 65 = 115 ∠DEB = 180 - 140 = 40 In ∆DEB ∠DBE + ∠DEB + ∠BDE = 180 ∠BDE = 180 - 40 - 115 = 25