Please help me! Santiago wants to walk at least 500 miles before the end of this year. He has already walked 437 miles, and there are 36 days left in the year. Which inequality can be used to find x, the number of miles he should walk each day to meet his goal?
a. 437 - 26x >= 500
b. 500 <= 36 + 437x
c. 437 + 36x >= 500
d. 500 <= 473x