You need an equation so that you need to add 3 to get the same value. Changing from 'x' to 'x - 3' requires a value (of the second expression) that is 3 larger than the entry in the first expression.
You need an equation so that you need to add 3 to get the same value. Changing from 'x' to 'x - 3' requires a value (of the second expression) that is 3 larger than the entry in the first expression.