Sam wants to paint his living room and he needs to buy some materials. Cans of paint cost $10 each and paint brushes each cost $2 each. If Sam plans to spend exactly $50 on painting materials, which of the following equations represents the number of cans of paint (c) and the number of paint brushes (b) that he can purchase?


A. $10c + $2b = $50
B. $10b + $2c = $50
C. $12(c + b) = $50
D. $2(5c × b) = $50