Answer:
unknown
Step-by-step explanation:
your question may be incomplete
The answer is C.) f^-1 (x) = 2x- 14 /
since the unknown amount can buy 100 pencils
he bought 70 pencils
therefore $4.50 can buy 30 pencils
so 1 pencils cost $4.50 /30=0.15
f = -5, s = -6
F= first number
S= second number
4f - s = -14
f + 3s = -23
3(4f - s = -14)
12f - 3s = -42
+ f + 3s = -23
13f = -65
————
13
f = -5
4(-5) - s = -14
-20 - s = -14
+20 +20
-s = 6
———
-1
s = -6
