Joey's mother gave him $50 to pay his friend for helping to clean-up their garage. He gave each friend $8 and still had $2 left. The equation 8x + 2 = 50 can be used to find the number of friends (x) that helped clean-up the garage. How many friends helped clean-up the garage?
A) 4
B) 6
C) 8
D) 9