The conversation between human and AI assistant.
[|Human|] Create an equation to represent the following phrase: the sum of twice a number and six.
[|AI|] The equation to represent the phrase "the sum of twice a number and six" can be written as:

2x + 6 = 0, where x is the unknown number.
[|Human|] 
Create an equation to represent the following phrase: the sum of twice a number and six.