BT2
a,42+19x=4
b,-12+5x=43
c,3x+37=16
d,18-5x=-12
e,-6x+33=-3
f,3x+11=17
g,4-14x=32
h,5x-25=-10
BT3
a,-(-12)-5+(+4)
b,-(-7)+(-14)-(-20)
c,(-13)-(-8)+(-15)
d,-16-(-9)-(+17)
e,/-7/-(17)-/17/
f,-/-13/+/-15/-(-5)
giup minh voi
BT2
a,42+19x=4
b,-12+5x=43
c,3x+37=16
d,18-5x=-12
e,-6x+33=-3
f,3x+11=17
g,4-14x=32
h,5x-25=-10
BT3
a,-(-12)-5+(+4)
b,-(-7)+(-14)-(-20)
c,(-13)-(-8)+(-15)
d,-16-(-9)-(+17)
e,/-7/-(17)-/17/
f,-/-13/+/-15/-(-5)
giup minh voi
42 + 19x = 4
19x = 4 – 42
19x = ( -38 )
-12 + 5x = 43
5x = 43 – ( -12 )
5x = 55
x = 55 : 5
x = 11
3x + 37 = 16
3x = 16 – 37
3x = -21
x = ( -21 ) : 3
x = -7
18 – 5x = -12
5x = 18 – ( -12 )
5x = 30
x = 30 : 5
x = 6
-6x + 33 = -3
-6x = ( -3 ) – 33
-6x = -36
x = ( -36 ) : ( -6 )
x = 6
3x + 11 = 17
3x = 17 – 11
3x = 6
x = 6 : 3
x = 3
4 – 14x = 32
14x = 4 – 32
14x = -28
x = ( -28 ) : 14
x = -2
5x – 25 = -10
5x = ( -10 ) + 25
5x = 15
x = 15 : 5
x = 3
BT3
– ( -12 ) – 5 + ( +4 )
= 12 – 5 + 4
= 7 + 4
= 11
– ( -7 ) + ( -14 ) – ( -20 )
= 7 + ( -14 ) – 20
= ( -7 ) – 20
= -27
( -13 ) – ( -8 ) + ( -15 )
= ( -13 ) – 8 + ( -15 )
= ( -21 ) + ( -15 )
= -36
-16 – ( -9 ) – ( +17 )
= ( -16 ) – 9 – ( -17 )
= ( -25 ) – ( -17 )
= -8
| -7 | – ( -17 ) – | 17 |
= 7 – ( -17 ) – 17
= 24 – 17
= 7
– | -13 | + | -15 | – ( -5 )
= 13 + ( -15 ) – ( -5 )
= ( -2 ) – ( -5 )
= 3
#ara boss ris
CHO MK XIN CTLHN Ạ
Bt2:
a) 42 + 19x = 4
⇒ 19x = -42 + 4
⇒ 19x = -38
⇒ x = -2
Vậy x = -2
b) -12 + 5x = 43
⇒ 5x = 43 + 12
⇒ 5x = 55
⇒ x = 11
Vậy x = 11
c) 3x + 37= 16
⇒ 3x = 16 – 37
⇒ 3x = 21
⇒ x = 7
Vậy x = 7
d) 18 – 5x= -12
⇒ 18+ 12 = 5x
⇒ 30 = 5x
⇒ x= 6
Vậy x= 6
e) -6x + 33= -3
⇒ -6x = -3 – 33
⇒ -6x = -66
⇒ x = 11
Vậy x = 11
f) 3x + 11= 17
⇒ 3x = 17 -11
⇒ 3x = 6
⇒ x = 2
Vậy x= 2
g) 4- 14x = 32
⇒ -14x = 32 – 4
⇒ -14x = 28
⇒ x = -2
Vậy x = -2
h) 5x – 25 = -10
⇒ 5x = -10 + 25
⇒ 5x = 15
⇒ x = 3
Vậy x= 3
BT3:
a,-(-12)-5+(+4)
⇒ 12 – 5 + 4 = 11
b,-(-7)+(-14)-(-20)
⇒ 7 – 14 +20 = 13
c,(-13)-(-8)+(-15)
⇒ -13 + 8 – 15 = 10
d,-16-(-9)-(+17)
⇒ -16 + 9 – 17 = -24
câu e) và f) là |-7| hay là /-7/ vậy bạn ? mong bạn trả lời ở dưới