Respuesta :

800
0.4(20-10x)=14x-28.

We move all terms to the left:

0.4(20-10x)-(14x-28)=0.

We add all the numbers together, and all the variables.

0.4(-10x+20)-(14x-28)=0.

We multiply parentheses.

-4x-(14x-28)+8=0.

We get rid of parentheses.

-4x-14x+28+8=0.

We add all the numbers together, and all the variables.

-18x+36=0.

We move all terms containing x to the left, all other terms to the right.

-18x=-36.

x=-36/-18.

x=+2.

Hope this helps. Brainliest?