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What is the remaining credit after 59 minutes of calls

What is the remaining credit after 59 minutes of calls-example-1
User A Spoty Spot
by
2.7k points

1 Answer

21 votes
21 votes

Let's find the equation of the line:

let:


\begin{gathered} (x1,y1)=(33,15.05) \\ (x2,y2)=(51,12.35) \end{gathered}

So:


m=(y2-y1)/(x2-x1)=(12.35-15.05)/(51-33)=-(2.7)/(18)=-0.15

So:


\begin{gathered} y-y1=m(x-x1) \\ y-15.05=-0.15(x-33) \\ y-15.05=-0.15x+4.95 \\ y(x)=-0.15x+20 \end{gathered}

After 59 minutes:


\begin{gathered} x=59 \\ y(59)=-0.15(59)+20 \\ y(59)=11.15 \end{gathered}

User Shajin
by
2.5k points
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