[ 308 - ( x - 6 ) ] . 15 = 1545
<=> 308 - x + 6 = 103
<=> 308 - x = 103 - 6 = 97
<=> x = 308 - 97 = 211
138 - 5 ( x + 4 ) = 38
<=> 138 - 5x -20 =38
<=> 138 - 5x = 38 + 20 = 58
<=> 5x = 138 - 58 = 80
<=> x = 16
308 - ( x - 6 ) = 1545 : 15
308 - ( x - 6 ) = 103
x - 6 = 308 - 103
x - 6 = 205
[ 308 - ( x - 6 ) ]. 15 =1545
[ 308 - ( x + 6 ) = 1545 / 15 = 103
x + 6 = 308 - 103
x = 205 - 6
x = 199
Vậy x = 199
138 - 5( x + 4 ) 38
5(x + 4 ) = 100
x + 4 = 20
x = 16
Vậy x = 16
1. [ 308 - ( x - 6 ) ] . 15 = 1545
308 - ( x - 6 ) = 1545 : 5
308 - ( x - 6 ) = 309
x - 6 = 309 + 308
x - 6 = 617
x = 617 + 6
x = 623
2. 138 - 5 ( x + 4 ) = 38
5 ( x + 4 ) = 138 - 38
5 ( x + 4 ) = 100
x + 4 = 100 : 5
x + 4 = 20
x = 20 - 4
x = 16
-Học tốt-
\(\left[308-\left(x-6\right)\right]\cdot15=1545\)
\(\Leftrightarrow308-\left(x-6\right)=1545:15\)
\(\Leftrightarrow308-\left(x-6\right)=103\Leftrightarrow x-6=208-103\)
\(\Leftrightarrow x-6=205\Leftrightarrow x=205+6\Leftrightarrow x=211\)
\(138-5\cdot\left(x+4\right)=38\Leftrightarrow5\cdot\left(x+4\right)=138-38\)
\(\Leftrightarrow5\cdot\left(x+4\right)=100\Leftrightarrow x+4=100:5\Leftrightarrow x+4=20\)
\(\Leftrightarrow x=20-4\Leftrightarrow x=16\)
