Answer:
3a. 8t + 12c = 72
3b. t + c = 7
Step-by-step explanation:
number of tapes is t
number of Cds is c
so 8t + 12c = 72
and t + c = 7
so t = 7 - c
replace t = 7 - c in to the first equation
8(7 - c) + 12c = 72
56 - 8c + 12c = 72
4c = 72 - 56 = 16
c = 4
if c = 4, then t = 7 - c = 7 - 4 = 3
F(n)=3n-2
Plug in 2 for n. f(2)=3(2)-2=4
-2x^2=-15-5
-2x^2=-10
x^2=-5
X≠R i am not quite sure but...hope it helps :)
