<PRE><B>Question 1122012</B>
Already explained in https://www.algebra.com/algebra/homework/Linear-equations/Linear-equations.faq.question.1122014.html


You really have  {{{(3/8)a-8=13}}}.

{{{(3/8)a=13+8}}}

{{{a=(13+8)(8/3)}}}, which you can compute mentally.



On a calculator, you can press buttons like this:
13 PLUS 8 EQUAL, MULT BY 8, DIV BY 3


or


(13) (+) (8) (=) (X) (8) (DIVIDEDBY) (3)
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