Question

∠BCD is an exterior angle of ∆ABC. If ∠BCD= 3∠A = x and ∠B = 80°, find the value of x.w

Answer 1

`\tt{✧ \: S \: O \: L \: U \: T \: I \: O \: N : }`

`\large{ \tt{✿ \: 3x = x + 80 \degree}}` [ Exterior angle is equal to the sum of two non - adjacent interior angles ]

`\longrightarrow \: \tt{3x - x = 80 \degree}`

`\longrightarrow \tt{2x = 80 \degree}`

`\longrightarrow \tt{x = (80 \degree)/(2) }`

`\longrightarrow{ \boxed{ \tt{x = 40 \degree}}}`

• Hence , the value of x is 40° .

Hope this helps! ( ╹▽╹ )