Answer:
a) 187.5 b) Domain c ∈ [0,187.5] c) Range ∈ [0,15]
Step-by-step explanation:
a) In this function, d stands for dollars and c stands for cookies. Ashley left $15 to pay supplies for making new cookies. The more cookies they made the less money it is left. For instance, If someone bakes 1 cookie using that money:
d=15-0.08c d=15-0.08(1) d=14.92 Then $14.92 is left after baking 1 cookie. And so on.
To find the zero of this function, let's turn this into an equation.
[tex]d=15-0.08c\\0=15-0.08c\\-15=-0.08c\\\ \frac{0.08}{0.08}c=\frac{15}{0.08}\\c=187.5[/tex]
So according to this function, with 15 dollars at least 187 cookies can be made.
b) The function d=15-0.08c if it was defined for the Real Set, any value would be valid within the Real Set. But c, is for cookies. Then the set is
[tex]Z_{+}[/tex]
[tex]d=15-0.08c\\0=15-0.08c\\-15=-0.08c\\\ \frac{0.08}{0.08}c=\frac{15}{0.08}\\c=187.5[/tex]
Domain c ∈ [0,187.5]
c) The Range
The Range is the subset of all values between $15 and 0$, since after the money is over they can no longer bake cookies. And there's $-1 dollar note.
So the Range is d ∈ [0,15]
