Helpppppp I’ll mark you brainlist

Answer
GCF is 1 and the x is
Multiples of 7 are: 7, 14, 21, 28, 35, 42, 49, 56, 63, 70, ... A common multiple is a whole number that is a shared multiple of each set of numbers. The multiples that are common to two or more numbers are called the common multiples of those numbers.