Question

One of the exterior angles of a triangle is 120° and the interior opposite angles of it are in the ratio 4 : 2. Find the angles of the triangle.​

Answer 1

Answer:

In the problem, you were given an exterior angle, d = 120°, and a remote interior angle (a or c, they’re interchangeable).

We know from linear pair theorem that b + 120° = 180°. So b = 60°

We can either use angle sum theorem or exterior angle theorem to find that last bad boy.

Angle sum theorem:

a + 60° + 30° = 180

a = 90°

Exterior angle theorem:

a + 30° = 120°

a = 90°

Thanks!!!! Hope you understand....

Answer 2

let the two unknown interior angles be 4 x and 2 x..

exterior  angle = opposite interior angles

120 ° = 4 x + 2 x

120 ° = 6 x

120 / 6 = x

20° = x

2 x = 40 °

4 x= 80 °

therefore the two interior angles are 40° and 80°

hope it helps !!