324 - (7.x - 18) . 5 = 99
7x - 18 . 5 = 324 - 99
7x - 18 . 5 = 225
7x - 18 = 225 : 5
7x - 18 = 45
7x = 45 + 18
7x = 63
x = 9
324 - ( 7. x -18) . 5= 99
( 7. x - 18) . 5= 324 - 99
( 7. x - 18 ) .5= 225
7. x -18 = 225 : 5
7 . x -180 = 45
7 . x = 45 + 18
7 . x =63
x = 63 : 7
x = 9
Vay x = 9