since k=3,one can substitute 3 for k in the equation
x−1
3
=k,which gives
x−1
3
=3. Multiplying both sides of
x−1
3
=3 by 3 given as x−1=9 and then adding 1 to both sides of x−1=9 and then adding 1 to both sides of x−1=9 gives x=10 Choices A, B, and C are incorrect because the result of subtracting 1 fromthe value and dividing by 3 is not the given value of k, which is 3.