Question

Can you please help me on 16, 17, 18 ,19, 20 I'm having problems on it☹️

Answer 1

16.

$S(4) \text{ it's like t=4, so} \Rightarrow S(4)=9\cdot 4-4=36-4=32$

17.

$S(4)$ determines how many people have swine in 4 days. But we know that $S(4)=32$. Hence, S(4) determines that in 4 days, there are 32 thousands people, who have swine already.

18.

$S(t)=23 \Rightarrow 23=9t-4 \Rightarrow t=3$

19.

$S(t)=23$ determines that in t days, there are 23 thousands people who have swine already. Since $t=3$. $S(t)=23$ determines that in 3 days, there are 23 thousands people who have swine already.

20. 

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