$a,15x-133= 17$
$15x = 17 + 133$
$15x = 150$
$x = 150 : 15$
$x = 10$
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$b,14x+ 54= 82$
$14x = 82 - 54$
$14x = 28$
$x = 28 : 14$
$x = 2$
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$c,17x- 20 = 14$
$17x = 14 + 20 $
$17x = 34$
$x = 34 : 17$
$x =2$
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