Answer:
see details and attached figure below.
Explanation:
Going row by row
1. 12 (isosceles triangles have equal legs from the vertex)
2. 55 deg. (isosceles triangles have equal base angles)
3. 90 = 180-45-45 (isosceles triangles have equal base angles)
4. 2x-8 = 10
=> x = 18/2 = 9 (isosceles triangles have equal legs from the vertex)
5. sum of angles of triangle = 180
3x+3x+2x+4 = 180 => 8x = 176, x = 22, angle A = 3x = 66 deg.
6. sum of angles of triangle = 180
(isosceles triangles have equal base angles)
25+25+angle Z = 180 => angle Z = 180-25-25 = 130