Question 1202446
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    a + (a-4) = 12

    2a - 4 = 12

    2a = 12 + 4

    2a = 16

     a = 16/2 = 8.


<U>ANSWER</U>.  Athena weights 8 pounds.
</pre>

Solved and presented in a form of a mantra to repeat it 
many times again and again for any other similar problem.



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It always touches me when I see a request "solve the problem by introducing variables in such and such a way."

Then I think where these people fell from.



Real teachers usually avoid to give instructions in Math at such micro-managing level.

Micro-managing in Math is the way to create a generations of students who will hate Math.