How to solve the equation 2 (x + 20) = 2.5x + 20?

2（x+20）=2.5x+20
2x+40=2.5x+20
2.5x-2x=40-20
0.5x=20
x=20÷0.5
x=40

3/5+1/5x=6/5

3/5+1/5x=6/5
First shift the term to get 1 / 5x = 3 / 5
Multiply left and right by 5 to get x = 3
I wish you a happy study

On the solution of the equation x + 1 / 2-0.5x-a / 0.3 = - 1 / 2 of X, then a=__

Substituting x = 1 into the equation yields
1-(0.5-a)/0.3=-1/2
1-(5-10a)/3=-1/2
6-2(5-10a)=-3
6-10+20a=-3
20a=1
a=1/20

How to solve the equation of 5x = 1.5

5x=1.5
x=1.5/5
x=0.3

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