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Question
Find the unknown marked angles in the given figure:
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Solution
In the figure,
∠A + ∠B + ∠C = 180° .....(Sum of angles of a triangle)
(m°− 5°) + 60° + (m°+ 5°) = 180°
⇒ m°− 5° + 60° + m° + 5° = 180°
⇒ 2m° = 180°− 65° + 5°
⇒ 2m° = 120°
⇒ ∴ m° = `(120°)/2=60°`
Hence ∠A = m°− 5° = 60°− 5° = 55°
and ∠C = m° + 5° = 60° + 5° = 65°
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