Question

an exterior angle of a triangle is 80 degree and one of the interior opposite angle is 30 degree find the other two angles of triangle​

Answer 1

Answer:

20° and 60°

Step-by-step explanation:

The angles on the inside are called Interior angles. The sum of the interior angles of a triangle is always 180 degrees. The exterior angle is the angle between any side of a shape, and a line extended from the next side. The sum of an exterior angle and its adjacent interior angle is also 180 degrees.........(1)

To understand the question first make a ∆ABC whose exterior angle from angle is C.  

let the multiple of the ratios be 'x'.

from above statement  (1)......

we have , 1x + 3x=80°

4x = 80° ⇒  x=80\4   ⇒ x=20°

from give  3x=20×3  and  3x=60°

Hence ,the two interior angles are 20° and 60°.