Iola has $75. She buys a pair of shoes on sale for one-half off and a pair of socks for $6. She has $32 left. Which equation can be used to find x, the regular price of the shoes?

a. x + 6 + 32 = 75
b. x + 6 = 32
c. 1/2x +6+ 32 =75
d. 1/2x +32 =75