Question

How do you solve `6x = 4x - ( - 18)`?

Answer 1

`x=9`

Explanation:

Simplify first as follows:

`6x=4x-(-18)`

`6x=4x+18`-----> opening the bracket

`6x-4x=4x-4x+18` -----> subtracting `4x` both sides

`2x=18`

`x=18/2`

`x=9`

Checking the answer:

`6(9) = 4(9) - (-18)`

`54 = 36+18` ----> Correct!

Answer 2

`x=9`

Explanation:

`"note that "-(-18)=+18`

`6x=4x+18`

`"subtract "4x" from both sides"`

`2x=18`

`"divide both sides by 2"`

`x=18/2=9`

`color(blue)"As a check"`

Substitute this value into the equation and if both sides are equal then it is the solution.

`"left side "=6xx9=54`

`"right side "=(4xx9)+18=36+18=54`

`x=9" is the solution"`

Answer 3

`x = 9`

Explanation:

`6x color(red)(=) 4x - (-18)` | you start with this

`6x color(red)(=) 4x - (-18)` | you put the '4x' on the other side
`6x-4x color(red)(=) - ( -18)`
`2x color(red)(=) - ( -18)`

`2x color(red)(=) - ( -18)` | -1 times -8
`2x color(red)(=) -1 (-18)`
`2x color(red)(=) 18`

`2x color(red)(=) 18` | put the 2 to the other side
`x color(red)(=) 18/2`
`x color(red)(=) 9`