a) 7 + (-x) = (-5) - (-14)
7 + (-x) = 9
-x = 9 - 7
-x = 2
x = -2
Vậy x = -2
b) 484 + x = (-632) + (-584)
484 + x = -48
x = -48 - 484
x = -532
Vậy x = -532
d) | x + 9 | = 12
x + 9 = 12
x = 12 - 9
x = 3
Vậy x =3
a) 7+(-x)=9 b) 484+x= (-632)+(-584)
x=9-7 484+X= -1216
x=2 X=(-1216)+484
X=-732
D) => X+9=12 HOẶC X+9= -12
TH1: TH2;
X+9=12 X+9= -12
X=12-9 X=-12-9
X=3 X=-21
a, 7 + (-x) = 9
-x = 9 - 7
-x = 2
=> x = -2
b, 484 + x = -1216
x = (-1216) - 484
x = -1700
c, 311 - x + 82 = 46 + x - 21
393 - x = 25 + x
393 - 25 = 2.x
368 = 2.x
=> x = 368 : 2 = 184
d, |x + 9| = 12
TH1 : x + 9 = 12 TH2 : x + 9 = -12
x = 12 - 9 x = (-12) - 9
x = 3 x = -21
a) 7 + (-x) = (-5) - (-14)
7 + ( -x ) = 9
-x = 2
x = -2
b) 484 + x = (-632) + (-584)
484 + x = -1216
x = -1700
c) 311 - x + 82 = 46 + (x - 21 )
311 - x + 82 = 46 + x - 21
-x - x = 46 - 311 - 21 - 82
-2x = -368
x = 184
\(d) | x + 9 | = 12\)
\(\orbr{\begin{cases}x+9=12\\x+9=-12\end{cases}}\)
\(\orbr{\begin{cases}x=3\\x=-21\end{cases}}\)