I think this is the Transitive postulate of equality.
Personally I can't see much point in giving labels to these equalities.
Answer:
6x + 2y
Step-by-step explanation:
0.04x -0.06y=0.48
x = 1.5y + 12
0.08x-0.11 y=0.92
x = 1.375y + 11.5
Hope this helps!
