Help with 5x-20=0 please

x= 4

I need to make an argument that like says how do we know no other values makes that equation true. In other words how do we know we are done?

You are also able to use the zero product property to be able to find the solution for x.
5x-20=0

5(x-4)=0

Now you divide each side by 5 to get rid of the 5

x-4=0

and now you know x is obviously 4

You could go along the lines of something like this...
You know that you are done because if you plug in 4 the answer comes out as 0 as stated in the equation. If you were to plug in anything else for x, it would not work.
Hope that helps.

5x-20=0

we moving 20 on the right

5x = 20

because get moving the negative change become positive

x = 20/5

x=4

i would like to say im sorry if my english is not good

Original equation:
5x - 20 = 0
Move 20 to the other side of the equal signs. We want x alone on one side so we can solve for it.
5x = 20
Now divide each side by 5
x = 4

5x - 20 = 0
5x = 20
x = 4.