The father of algebra

Diophantus, and Alexandrian Greek mathematician, is considered as the father of Algebra, he wrote the series Arithmetica, where he deals with some algebraic equations, it was a collection of thirteen books, but nowadays, there are only six left. Those thirteen books had a total of 130 exercises about determinate and indeterminate equations. A curious fact of Diouphantus: his Epitaph says:

Cover of a 1621 edition

'Here lies Diophantus,' the wonder behold.

Through art algebraic, the stone tells how old:

'God gave him his boyhood one-sixth of his life,

One twelfth more as youth while whiskers grew rife;

And then yet one-seventh ere marriage begun;

In five years there came a bouncing new son.

Alas, the dear child of master and sage

After attaining half the measure of his father's life chill fate took him. After consoling his fate by the science of numbers for four years, he ended his life.'

If we write the puzzle, and solve for "x", it will give us that his age was 84.

x = x/6 + x/12 + x/7 + 5 + x/2 + 4 = 84