Is this a function or not a function?

Tod does not have any cookies. david gives jeff 8 cookies. then he splits half of the cookies he has left with tod. david let’s c represent the number of cookies that he starts with. he finds the number of cookies that tod has is 1/2 the difference of c and 8. write an expression to represent the number of cookies that tod has.

Which of these angles are supplementary? a. 100o and 90o b. 78o and 102o c. 54o and 146o d. 12o and 78o

Felix wrote several equations and determined that only one of the equations has no solution. which of these equations has no solution?