(x - 3)·(x - 2) = x·(x - 6)
x^2 - 5·x + 6 = x^2 - 6·x
6·x - 5·x = -6---> x = -6
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$\small (x-3)(x-2) = x(x-6)$
$\small x^2-2x-3x+6 = x^2-6x$
$\small x^2-5x+6 = x^2-6x$
$\small \cancel{x^2}-\cancel{x^2}-5x+6x = -6$
le due incognite al quadrato si annullano per via del segno opposto, quindi:
$\small x = -6$
x^2-2x-3x+6=x^2-6x -5x+6=-6x 6x-5x=-6 x=-6
x^2 - 5x + 6 = x^2 - 6x
6x - 5x = -6
x = -6