Collin noticed that various combinations of nickels and dimes could add up to $0.65. let x equal the number of nickels let y equal the number of dimes what is the domain where y is a function of x and the total value is $0.65?

Defining variables we have:
 y = the number of dimes
 x = the number of nickels
 0.05x + 0.1y = 0.65
 We clear y:
 y = (- 0.05x + 0.65) / (0.1)
 y = -0.5x + 6.5
 The domain will be:
 (0, 13)
 
 the domain where and is a function of x is:
 (0, 13)
 and the total value is $ 0.65 when
 x = 1
 y = 6

The answer is option c.