3 * ( x - 9) + 15 = 12 + 243 : 9
3 * ( x - 9 ) + 15 = 39
3 * ( x- 9 ) = 39 - 15
3 * ( x - 9 ) = 24
x - 9 = 24 : 3
x - 9 = 8
x = 8 + 9
x = 17
Vậy...
^^ Cbht!!!
3*(x-9)+15=12+243:9
3*(x-9)+15=12+27
3*(x-9)+15=39
3*(x-9)=39-15
3*(x-9)=24
x-9=24:3
x-9=8
x = 17
502-(x+5):2=318
(x+5):2=502-318
502-(x+5)=636
(x+5):2=184
(x+5)=184*2
(x+5)=368
x=363
120+[(999-9x):60]:24
3 * ( x - 9 ) + 15 = 12 + 243 : 9
3 * ( x - 9 ) + 15 = 12 + 27 = 39
3 * ( x - 9 ) = 39 - 15 = 24
x - 9 = 24 : 3 = 8
x = 8 + 9
x = 17 .
502 - ( x + 5 ) : 2 = 318
( x + 5 ) : 2 = 502 - 318 = 184
x + 5 = 184 x 2 = 368
x = 368 - 5
x = 363 .
120 + [ ( 999 - 9x ) : 60 ] : 24 = ?