Final answer:
To factor the expression 7x - 7, the GCF is 7, resulting in the factorization 7(x - 1), which is answer choice 'a'.
Step-by-step explanation:
To factor the expression 7x - 7 by using the Greatest Common Factor (GCF), you need to identify the largest number that divides both terms. In this case, the GCF is 7. Factoring out the GCF, the expression becomes 7(x - 1). This corresponds to answer choice 'a' in your options.
To confirm that this factorization is correct, you can distribute the factor back into the parentheses: 7 × x gives us 7x, and 7 × -1 gives us -7. Adding these two terms together gets us back to our original expression, confirming that the factorization is reasonable and correct.