Question

if angles of the triangle are in ratio 3:4:5 than the smallest angle is option a) 15° b)60° c)45° d)30°

Answer 1

Hola there,

Ratio of angles = 3:4:5

Let 1st Angle be = 3x
2nd Angle be = 4x
3rd Angle be = 5x

By Angle sum property of triangle we can say that,

=> 3x + 4x + 5x = 180°

=> 12x = 180°

=> x = 15°

So,

1st Angle = 3×15° = 45°

2nd Angle = 4×15° = 60°

3rd Angle = 5×15° = 75°

So, smallest Angle = 45°

Ans: Option (c) 45°

Hope this helps...:)

Answer 2

The answer is c) 45°

Explanation:
The angles are in the ratio 3:4:5
Let the angles be 3x, 4x and 5x.
By using angle sum property of a triangle we get :
3x+4x+5x=180
=> 12x = 180
=> x = 180/12 =15.
So, the angles are 3x = 3×15 = 45°
4x =4×15=60°
5x = 5×15 =75°
Therefore, the smallest angle is 45°.