Question 444146
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6x - y = 39
6x + 7y=33
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As I look at the solution in the post by @matanth, his solution evokes a feeling of protest in me,
because, strictly speaking, it is incorrect.

Using decimal numbers with two digits after the decimal dot, he found the solution x = 6.38, y = -0.75.


While the 'y'-value is precise, 'x'-value is approximate.


The exact 'x'-value is 6.375,  so the exact solution is  (x,y) = (6.375,-0.75).


As I see, the computer code, which @manath uses for his calculations, is very restricted
and does not make a selection, which form to use - in rational numbers or in decimals,
and always prints the output decimals with 2 decimal digits.


In many cases, it leads to incorrect/erroneous solution.


A good code (I mean, a truly good code) must be much smarter and much more flexible,
with built-in-brain.