Angles of a triangle are in the ratio 2: 4: 3. The smallest angle of the triangle is
Let us draw a ΔABC.
It is given that the angles of the triangle are in the ratio 2: 4: 3.
Let us assume,
∠A = 2x, ∠B = 4x, ∠C = 3x - - - - (i)
We know that the sum of the angles of a triangle is equal to 180°.
So, ∠A + ∠B + ∠C = 180°
⇒ 2x + 4x + 3x = 180° [From equation (i)]
⇒ 9x = 180°
⇒ x = 20° - - - - (ii)
From equation (ii), we get
∠A = 2x = 2 × 20° = 40°
∠B = 4x = 4 × 20° = 80°
∠C = 3x = 3 × 20° = 60°
From above, we find that the smallest angle, ∠A is 40°.
Thus, option (B) is correct.
Option (A) is not correct. The smallest angle is not 60° this is because the smallest angle is ∠A which is 40°. So, the smallest angle of the triangle is not 60°.
Option (C) is not correct. ∠B measures 80° which is the largest angle of the triangle. So, the smallest angle of the triangle is not 80°.
Option (D) is not correct. 20° is not the correct angle for any of the angles of the triangle. So, the smallest angle of the triangle is not 20°.