Tick the correct answer and justify : In ∆ABC, AB = 6√3 cm, AC = 12 cm and BC = 6 cm. The angle B is :
(A) 120° (B) 60° (C) 90° (D) 45°
AB = 6√3 cm; AC = 12 cm; BC = 6 cm
AB2 = 108 cm2; AC2 = 144 cm2; BC2 = 36 cm2
AB2 + BC2 = (108 + 36) cm2
= 144 cm2
⇒ AC2 = AB2 +BC2
Pythagoras theorem satisfied. Thus, ∠ABC = 90°
Therefore, option (C) 90° is the correct answer.
Tick the correct answer and justify : In ∆ABC, AB = 6√3 cm, AC = 12 cm and BC = 6 cm. The angle B is : (A) 120° (B) 60° (C) 90° (D) 45°
NCERT Class 10 Maths Solutions Chapter 6 Exercise 6.5 Question 17
For the given ∆ABC, AB = 63 cm, AC = 12 cm and BC = 6 cm. The angle B is 90 degrees.
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