Question

an exterior angle of triangle is 120 and one of the interior opposite angle iz 40. find other two angles of triangle
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Answer 1

Step-by-step explanation:

HEY MATE

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There are three relevant theorems to help us here:The angle sum theorem: a + b + c = 180° (interior angles of a triangle sum to 180°)The linear pair theorem: b + d = 180° (linear pairs are supplementary)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° = 180a = 90°Exterior angle theorem:a + 30° = 120°a = 90°

Answer 2

Answer:

if one exterior angle is 120°

then, the interior angle on the adjacent side=(180-120)° =60°

now, solve like this,

According to Angle Sum Property of Triangle

60°+40°+x°=180°

100°+x=180

x=80°

so the other two angles are

60° and 80°