How do you write x-6 in verbal expression

x is just a stand-in for an unknown/variable number, so we could use phrases like "a number," "a value," "an unknown," etc. Here, I'll use "a number." We can verbally refer to the result of subtraction as "the difference" as well, so we can write x - 6 in English as "The difference of a number and 6."

i believe that the answer is

b. y-1=-2(x-4)

hope this !