6.9*x-6=9

We have 6.9*x-6=9, and we need to solve for x.

6.9*x-6=9

        +6   +6          ---Add 6 to both sides, we can do this as long as we make sure to do it to both sides.

6.9*x = 15            

÷6.9      ÷6.9          ---Divide both sides by 6.9. Again, this works aslong as it is done to both sides of the equation.

Now we are left with:

x = 2.173913

or we can round this up to 

x = 2.2

 

Let's check it. To check it, we can put in 2.173913 for x, because x = 2.173913.

6.9*(2.173913)-6=9

14.999999-6 = 9           ---14.999999 is sooo close to 15, that we can round it up to 15.

15-6=9

9=9 ✔

 

9 does equal 9, so our answer is right!