Question

tim x biet:

a) x+7=-5-14

b)3x-4=(-2)mu3 - 11

c)11+(4x-11)=-9-(-15)

d)|2x-1|=5

e) |x-7|+3=25

giup minh nhe

hom nay nop roi

Answer 1

1.a)x+7=-5-14

x+7=-19

x=-19-7

x=-26

Vậy x=-26

b)3x-4=(-2)³-11

3x-8=-11

3x=-11+8

3x=-3

x=-3:3

X=-1

Vậy x=-1

c)11+(4x-11)=-9-(-15)

11+(4x-11)=-9+15

11+(4x-11)=6

4x-11=6-11

4x=6

x=\(\dfrac{6}{4}\)

Vậy x=\(\dfrac{6}{4}\)

d)\(\left|2x-1\right|=5\)

⇒2x-1=\(\pm5\)

+Nếu 2x-1=5

2x=6

x=6:2

x=3

Vậy x=3

+Nếu 2x-1=-5

2x=-5+1

2x=-4

x=-4:2

x=-2

Vậy xϵ{3;-2}

e)\(\left|x-7\right|+3=25\)

\(\left|x-7\right|=22\)

⇒x-7=\(\pm22\)

+Nếu x-7=22

x=22+7=29

+Nếu x-7=-22

x=-22+7

x=-15

Vậy xϵ{29;-15}