Find the value of f(9) and g(–9) if f(x) = –7x – 9 and g(x) = 6x3 – 23x.
f(9) = –16
g(–9) = –760

f(9) = –54
g(–9) = 16764

f(9) = –72
g(–9) = –4167

f(9) = 63
g(–9) = 54

For this case we have the following functions:

We must find and

Substituting we have:

On the other hand:

Option C

21

jk it's 20

step-by-step explanation:

answer: 8 years

step-by-step explanation:

the explanation is that in 8 years the child will be 20 and in 8 years the father will be 40 and 20 is half of 40.