In a right-angled triangle, one of the legs is 3 m, and the hypotenuse is 6 m. Find the sharp corners of this triangle.

There is a theorem.
In a right-angled triangle opposite an angle of 30 degrees lies a leg equal to half of the hypotenuse.
Hypotenuse by condition 6 m.
Known leg 3 m.
This means that an angle of 30 degrees lies opposite it.
One angle of a straight line is 90 degrees.
Since in a triangle, the sum of the angles is always 180 degrees.
The third angle will be 60 degrees.