For this case we must raise an inequality.
We have "d" dollars initially and they are spent 12. Then:

At least 51 dollars remain, then, the sign of inequality is greater or equal in favor of the expression
, that is:

Resolving:

There are at least 63 dollars left in the account.
Answer:

Final Answer M= 4,12 i think this is adding
In rectangle : US=RT
2SO=US
6x+4=14x-12
X=16/8
6(16/8)+4=your answer
3×6/8 reduce is 3× 3/4= 3/1×3/4=9/4 or 2 1/4