2x=5+7
2x=12
x=12:2
x=6
2x - 7 =5
2x= 5+7
2x=12
x-12:2
x=6
128-3.(x+4)= 23
3.(x+4) = 128-23
3.(x+4)= 105
x+4=105:3
x+4=35
x=35-4
x=31
2x-7=5 128-3.(x+4)=23
=>2x=5+7 =>3.(x+4)=128-23
=>2x=12 =>3.(x+4)=105
=>x=12:2 =>x+4=105:3
=>x=6 =>x+4=35
=>x=35-4
=>x=31
b1 tìm x ,biết
(x-14)-20=5
128+(202-x)=330
(x-120)*9=450
x-320:32=25*16
25-(2x+10)=5
315-(135-x)=215
x:2+21:3=37
4*(x+100)=800
504:(16-5x)=72
(x-5):7+3=20
mik cảm ơn nhaa
a)5. ( x + 35 ) = 515
b) (x+7):3=14c) 72:(x–15)=8
d) 19+(x+23)=50
e) (18–x) + 23 =29
f) 56–(x+14)=22g) (2x +1)–7=14
h) 3. (x+1)–32=67i) 70–5. (x–3)=45
j) 200–8. (2x+7)=112
k) 123–(x+4). 5 =38
a/713:(2x+17)=23
b/(x+4/3)*7/4=5-7/6
2x+23=37:34
[(4x+28).3+55]:5=35
17-(3x+9)=2-(-3+x)
(12x-43).83=4.84
720:[41-(2x-5)]=23.5
128-3.(x+4)=23
Tìm số nguyên x, biết:
1) -16 + 23 + x = - 16
2) 2x – 35 = 15
3) 3x + 17 = 12
4) (2x – 5) + 17 = 6
5) 10 – 2(4 – 3x) = -4
6) - 12 + 3(-x + 7) = -18
Bài 1A) 12-(23-17) |-15|=(3-x)-23-8|-9|)B)15-(5 x)=7-|-4| (5-9 |-6|-15)Bài 2A) (3x 2)^3=-64B) 2x-3=-33
Tìm số tự nhiên x biết
a) 4 mũ 2x - 3 + 7 . 4 mũ 3 = 4 mũ 3 . 23
b) 3600 : [ ( 5x + 335 ) : x ] = 50
Tim X
3) -12 + (2x – 9) + x= 0
4) 11 + (15 - x) = 1
5) 4 - (27 - 3) = x - (13 - 4)
6) 8 - (x - 10) = 23 - (- 4 +12)
7) 105 – 5(10 – 5x) = -20
8) (x -1)(8-2x)(3x+123) = 0
9) (x2 - 25)(x+ 10) = 0
10) x(x2+5) =
Tìm x
1)2x+3x–4x=(-2)3
2)x–2x=42+40
3)23x–32x=/12–21/
4)x–45=2x+54
5) 5x–12+23=67:65
