Add 2.2 to each side so 0.3z = 5.2 - 0.5z -0.8z
add 0.5z to each side so 0.8z = 5.2 - 0.8z
add 0.8z to each side so 1.4z = 5.2
divide each side by 1.4 so z = 3.71428571
AAS and SAA don't prove congruence.
You can have two triangles that have AAS or SAA and are not congruent.
From this picture, these triangles are congruent by ASA .