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Write an equation of the line that passes through each pair of points.(5, −2), (7, −1)

User Mayelin
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2 Answers

3 votes

Answer:

y=1/2x-9/2

Explanation:

First you want to find the slope by doing -2-(-1)/5-7

Therefore the slope is 1/2

Next you want to add in any set of points, either (5, -2) or (7, -1)

Substitute the x- point in place of x and the y in place of y in y=1/2x+b

Once you do this you should get -2=1/2(5)+b

You should get -2=2 1/2+b

Then subtract 2 1/2 from -2

You should get -4 1/2

Once you have the slope and y- intercept you can put together your problem

y=1/2x-4 1/2

don't forget to convert, y=1/2x-9/2

Hope this helps

User Beached
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6.0k points
1 vote


(\stackrel{x_1}{5}~,~\stackrel{y_1}{-2})\qquad (\stackrel{x_2}{7}~,~\stackrel{y_2}{-1}) ~\hfill \stackrel{slope}{m}\implies \cfrac{\stackrel{rise} {\stackrel{y_2}{-1}-\stackrel{y1}{(-2)}}}{\underset{run} {\underset{x_2}{7}-\underset{x_1}{5}}} \implies \cfrac{-1 +2}{2} \implies \cfrac{ 1 }{ 2 }


\begin{array}ll \cline{1-1} \textit{point-slope form}\\ \cline{1-1} \\ y-y_1=m(x-x_1) \\\\ \cline{1-1} \end{array}\implies y-\stackrel{y_1}{(-2)}=\stackrel{m}{ \cfrac{1 }{ 2 }}(x-\stackrel{x_1}{5}) \implies y +2 = \cfrac{1 }{ 2 } ( x -5) \\\\\\ y+2=\cfrac{1 }{ 2 }x-\cfrac{5 }{ 2 }\implies y=\cfrac{1 }{ 2 }x-\cfrac{5 }{ 2 }-2\implies {\Large \begin{array}{llll} y=\cfrac{1 }{ 2 }x-\cfrac{9}{2} \end{array}}

User Imara
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