At least one angle in the triangle is greater than or equal to: 45 degrees, 55 degrees, 60 degrees, 65 degrees?

Counter proof: if none of the three angles is greater than or equal to 60, then the sum of the three angles is less than (60 + 60 + 60) = 180
The sum of the inner angles of the triangle is 180
So the assumption is wrong
So: at least one of the three internal angles of a triangle is greater than or equal to 60

There is a triangle with two angles: 20 degrees and 65 degrees. What triangle is it?
I forgot to take my math book and I don't understand this problem. Thank you for your trouble

The two angles are 20 degrees and 65 degrees
Then the third angle is 180-20-65 = 95 degrees
So, it's an obtuse triangle

A triangle with an angle of 65 degrees is a body triangle. What kind of triangle is it?

Right triangle, acute triangle and obtuse triangle are all possible
If the triangle is an isosceles triangle, then it must be an acute triangle

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At least one angle in the triangle is greater than or equal to: 45 degrees, 55 degrees, 60 degrees, 65 degrees?