Answer:
x = 9
y = 3
z = 3
Explanation:
Triangle 1 (From the left):
5x + 7x = 13x - 9 (Sum of two interior angles of a triangle is equals to exterior opposite angle)
Grouping like terms we have:
12x - 13x = - 9
x = 9
Triangle 2 (From the left):
30y = 90 (angles at a right angle = 90)
y = 3
Triangle 3 (From the left):
15z + 12z + 36 = 39z
36 = 39z - 27z
z = 36/12
z = 3