120 - 180 : ( x - 12 ) + 60 = 0
120 - 180 : ( x -12 ) = - 60
180 : ( x - 12 ) = 180
x - 12 = 1
x = 13
Chúc bạn học tốt.
180 : (X-12)+60=120
180 : (X-12) = 120 -60
180 : (X-12) = 60
X-12 = 180 : 60
X-12 = 3
X = 3 + 12
X = 15
120-180:(X-12)+60=0
180:(x-12)+60=120-0=120
180:(x-12)=120-60=60
x-12=180:60=30
x=30+12=42
120 - 180 : ( X - 12 ) + 60 = 0
<=> 120-180:(X -12) = -60
<=> 180:(X-12) =120 + 60
<=> 180:(X-12) = 180
<=> X- 12 =180 : 180
<=> X -12 = 1
<=> X = 1 + 12
<=> X =13 (k cho minh nha )