Answer:
x = 35, y = 145, z = 25
Explanation:
All triangles' angles have a sum of 180°. Because we know this, we can solve the first triangle easily.
180 = x + 90 + 55
180 = x + 145
35 = x
Angles x and y are what we call suplementary angles. This means they have a sum of 180°.
180 = 35 + y
145 = y
Once again, we know that triangles have a sum of 180°. So the next triangle should now be easy to solve.
180 = 10 + 145 + z
180 = 155 + z
25 = z