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find an equation of the line passing through the pair of points. write an equation in the form Ax+By=C (3,1) and (5,7)

User Bill Huertas
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1 Answer

21 votes
21 votes

The two points given are:


\begin{gathered} (x_1,y_1)=(3,1) \\ \text{and} \\ (x_2,y_2)=(5,7) \end{gathered}

Let's find the slope, m, first:


\begin{gathered} m=(y_2-y_1)/(x_2-x_1) \\ m=(7-1)/(5-3) \\ m=(6)/(2) \\ m=3 \end{gathered}

We can now use the point slope form of a line to figure out the equation. Process is shown below:


\begin{gathered} y-y_1=m(x-x_1)_{} \\ y-1=3(x-3) \\ y-1=3x-9 \\ y=3x-9+1 \\ y=3x-8 \end{gathered}

We re-arrange in the form Ax + By = C,


\begin{gathered} y=3x-8 \\ -3x+y=-8 \end{gathered}

User Jimmy Ilenloa
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