Just look at the top triangles
Angles in a triangle add up to 180°
To find the angle next to 36°:
It shows that all together its a 90° angle so you do 90-36= 54°
To find the angle next to 88°:
Angles on a straight line add up to 180° so you do 180-88= 92°
You now have the 2 of the angles in the triangle with angle 1
You now add these 2 angles so 54+92= 146°
and as angles in a triangle add up to 180° you do 180-146= 34°
So angle 1 is 34°