Question

Tìm x biết

a,|2x-1|=|x+2|

b,x+2/5=2-3x/3

c,2.3^x.3^2=18

 

Answer 1

b) x + 2/5 = 2-3x/3

x + 2/5 = 2 -x

x +x = 2 - 2/5

2x= 8/5

x = 8/5 x 1/2

x = 4/5

Answer 2

c) 2. 3^x . 3^2 = 18

3^x+2 = 18:2

3^ x+2 = 9

3^ x+2 = 3^2

=> x+2 = 2

=> x=0

Answer 3

a) TH1: 2x-1 = x + 2

2x-x = 2+1

x =3

TH2 : 2x-1 = -(x+2)

2x-1 = -x-2

2x +x = -2 +1

3x = -1

x = -1/3