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A line includes the points (10,1) and (a,-5) has a slope of 1/3. What is the value of a?

User Fosho
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1 Answer

6 votes

For this case we have that by definition, the slope of a line is given by:


m = \frac {y_ {2} -y_ {1}} {x_ {2} -x_ {1}}

Where:


(x_ {1}, y_ {1})\ and\ (x_ {2}, y_ {2})are two points through which the line passes.

According to the statement we have:


(x_ {1}, y_ {1}) :( 10,1)\\(x_ {2}, y_ {2}) :( a, -5)\\m = \frac {1} {3}

Substituting we have:


\frac {1} {3} = \frac {-5-1} {a-10}\\\frac {1} {3} = \frac {-6} {a-10}\\a-10 = \frac {-6} {\frac {1} {3}}\\a-10 = -18\\a = -18 + 10\\a = -8

Thus, the value of a is -8.

Answer:


a = -8

User Bloke
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