As per given by the question,
There are given tha a right angle triangle and ,
The given angle is;

Now,
The sum of the angles in triangle is 180 degree. A right triangle has one angle of 90 degree.
So,
The sum of the other two angle will be 90 degree.
Then,
From triangle MNL;

Fro above equation, find the value of x;

Then,

So, the value of x is 8.
Now,
For the angle L,
Put the value of x in equation of angle L,

For the angle M,

Now,
For the angle N;
The angle N is,

Hence, the value of x is 8, and the angle L is 55 degree, angle M is 35 degree, and the angle N is 90 degree,