Question

One of the interior opposite angles of a triangle is 40°. If the measure of the exterior

angle is 120°, find the measure of the other two angles of the triangle.

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Answer 1

Answer:

120° =40° +x

so

x=80°

now third angle of triangle is =180-120=60°

so angles are 40,60,80

hope it helped :)

Answer 2

Exterior angle = sum of opposite interior angles

Let the other opposite interior angle be x.

120 = 40 + x

x = 120 - 40

x = 80°

Sum of all angles in a triangle is 180°

Let the other angle in the triangle be y

40 + 80 + y = 180

120 + y = 180

y = 180 - 120

y = 60°

Answer: The other 2 angles are 80° and 60°