Holly evaluated an expression and showed her work. Which comment about Holly's solution is correct?

a

step-by-step explanation:

u take $30 minus $24. the answer/original($30)

sample answer: you can determine whether each element of the domain is paired with exactly one element of the range. for example, if given a graph, you could use the vertical line test; if a vertical line intersects the graph more than once, then the relation that the graph represents is not a function.