Answer:
2(x-3) = 8
Step-by-step explanation:
first it says 'difference of a number and 3' so that equals to (x-3), we use 'x' for the variable for the unknown number
next it says 'twice', so two times which equals 2(x-3)
last it says 'is 8', which means 'equals' so "2(x-3) = 8"