Find the acute corners of a right-angled triangle if its outer angle is 120 (degrees).

As we know from the existing school geometry curriculum, the outer corner complements the inner corner of the triangle to an unfolded one.

Let us determine through what number of degrees it is possible to represent the angle of the triangle, when from the condition of the task we know that its external angle is 120 °:

180 – 120 = 60.

Let us determine through what number of degrees it is possible to represent another angle of the triangle, when from the condition of the task we know that the triangle is rectangular:

90 – 60 = 30.

Answer: 60 ° and 30 °.



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