Answer:
x = 13; y = 13; z = 18
Explanation:
In a rhombus, opposite angles are congruent and consecutive angles are supplementary.
6x + 8 = 86
6x = 78
x = 13
7y + 3 + 86 = 180
7y + 89 = 180
7y = 91
y = 13
5z + 4 + 86 = 180
5z + 90 = 180
5z = 90
z = 18