các bn lm giúp mk,mk cảm ơn ạ

Bài 2: 

=>5x+2x+0,3=2,4

=>7x=2,1

hay x=0,3

ét o ét các bn lm giúp mk ik,mk đang cak gấp ạ

Bài 2: 

5x-(-2x-0,3)=2,4

=>5x+2x+0,3=2,4

=>7x=2,1

hay x=0,3

a: \(2,5:4x=0,5:0,2\)

=>\(2,5:4x=0,5\cdot5=2,5\)

=>4x=1

=>\(x=\dfrac{1}{4}\)

b: \(3,8:2x=\dfrac{1}{4}:2\dfrac{2}{3}\)

=>\(3,8:2x=\dfrac{1}{4}:\dfrac{8}{3}=\dfrac{1}{4}\cdot\dfrac{3}{8}=\dfrac{3}{32}\)

=>\(2x=3,8:\dfrac{3}{32}=\dfrac{19}{5}\cdot\dfrac{32}{3}=\dfrac{608}{15}\)

=>\(x=\dfrac{608}{15}:2=\dfrac{304}{15}\)

c: \(5,25:7x=3,6:2,4\)

=>\(5,25:7x=1,5\)

=>\(7x=5,25:1,5=3,5\)

=>\(x=\dfrac{3.5}{7}=0,5\)

d: \(1,8:1,3=-2,7:5x\)

=>\(5x=-2,7:\dfrac{18}{13}=-2,7\cdot\dfrac{13}{18}=-1,95\)

=>\(x=-1,95:5=-0,39\)

2x-5=(x-7)+(12-5x)

2x-5=x-7+12-5x

=>2x-x+5x=-7+5+12

      x+5x=-2+12

      6x    =10

=>x=10:6

   x=10/6=5/3

Vậy x=5/3

Hok tốt

\( 2x - 5 = \left( {x - 7} \right) + \left( {12 - 5x} \right)\\ \Leftrightarrow 2x - 5 = x - 7 + 12 - 5x\\ \Leftrightarrow 2x - 5 = - 4x + 5\\ \Leftrightarrow 2x + 4x = 5 + 5\\ \Leftrightarrow 6x = 10\\ \Leftrightarrow x = \dfrac{{10}}{6} \)

3,26 + 4/5 =?

làm nhanh lên giúp mình nhé

3,26+4/5=3,26+0,8=3,34

K cho mình cái

2x - 5x = 6 + 3

-3x       = 9

x          = 9 : -3

x          = -3

=> 5x+6 - (2x-3) = 0

=> 5x+6 - 2x +3 = 0

=> 3x + 9 = 0

=> 3x = 0- 9 = -9

=> x = -9 : 3 = -3