Consider the offered option:
if suppose, that unknown side is '?', then
2*(3x-3)+2*'?'=10x+6;
6x-6+2*'?'=10x+6;
2*'?'=4x+12;
'?'=2x+6
Answer: 2x+6
.8 it represents .80 cents. rather than .08 which would represent 8 pennies
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