a ,$ ( 27 . x + 6 ) : 3 - 11 = 9$
$( 27 . x + 6 ) : 3 = 9 + 11$
$( 27 . x + 6 ) : 3 = 20$
$27 . x + 6 = 20.3$
$27 . x + 6 = 60$
$27x = 60 - 6$
$27x = 54$
$x = 54 : 27$
$x = 2$
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$( 15 - 6x ) . 3^5 = 3^6$
$15 - 6x = 3^6 : 3^5$
$15 - 6x = 3 $
$6x =15- 3 $
$6x = 12$
$x = 12 : 6$
$x = 2$
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$740 : ( x + 10 )= 10² - 2 . 13$
$740 : ( x + 10 )= 100 - 26$
$740 : ( x + 10 )= 74$
$x+10= 740 : 74$
$x+10 = 10$
$x =10 -10$
$x = 0$
