Answer:
x = 6.
y = 6.7.
z = 13.4.
Step-by-step explanation:
The 2 triangles contained in the biggest one are similar, so:
x/12 = 3/x
x^2 = 36
x = 6.
Applying the Pythagoras theorem:
z^2 = 6^2 + 12^2
z^2 = 36 + 144 = 180
z = 13.4.
y^2 = x^2 + 3^2
= 36 + 9
= 45
y = 6.7
