a, 2x+15=67-(-18) b, 4x-12=3x-(-7) c, 2|x-1|+3=13
2x+15=67+18 4x-12=3x+7 2|x-1| = 13-3
2x+15= 85 4x-3x = 12+7 2|x-1| =10
2x =85-15 x = 19 |x-1| = 10:2
2x = 70 |x-1| = 5
x = 70:2 +) Nếu x=5 thì x-1=5 suy ra x=6
x = 35 +) Nếu x=-5 thì x-1= -5 suy ra x= -4
a, 2x + 15 = 67-(-18)
=> 2x + 15 = 67 + 18
=> 2x = 85 - 15
=> 2x = 70
=> x = 35
b, 4x - 12 = 3x-(-7)
=> 4x - 12 = 3x + 7
=> 4x - 3x = 7 + 12
=> x = 19
c, 2|x - 1| + 3 = 13
=> 2|x - 1| = 10
=> |x - 1| = 5
=> x - 1 = 5 hoặc x - 1 = -5
=> x = 6 hoặc x = -4
a) 2x + 15=67+18 b)4x-12=3x+18 c) 2|x-1|+3=13
2x +15=85 4x-3x=12+18 2|x-1|=13-3
2x=85-15 1x =30 2|x-1|=10
2x=70 x=30:1=>x=30 |x-1|=10:2
x=70:2 =>x=45 |x-1|=5=> x=5 hoặc x= -5
x-1=5=>x=5+1=>x=6
x-1=5>x=-5+1=>x=-4
câu b mình ko hỉu lắm! chúc bạn hok tốt
