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34 votes
34 votes
The points (v,-3) and (8,5) fall on a line with a slope of -8. what is the value of v?

User Roland Weber
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1 Answer

20 votes
20 votes

The slope m is given by:


\begin{gathered} m=(y2-y1)/(x2-x1) \\ \text{Where:} \\ (x1,y1)=(v,-3) \\ (x2,y2)=(8,5) \\ m=-8 \\ so\colon \\ -8=(5-(-3))/(8-v) \\ \text{solve for v:} \\ -8(8-v)=5+3 \\ -64+8v=8 \\ 8v=72 \\ v=(72)/(8) \\ v=9 \end{gathered}

User Nomade
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