Hello friends today we are going to discuss the topic **How To Find The Equation Of A Line**, for finding the equation of a line we need to have the knowledge of the three parameters but before talking about the parameters we will be seeing that what actually is the equation of line,

Y = mx +c

(know more about Linear equation, here)

With the help of this equation we can the equation of line passing through two points with a slope, the direction of x will always be horizontal and the direction of y will always be vertical, in the above equation m is the slop of the given line, if a line passing through the origin then its equation will be

Y = mx

If the value of m is 3 then the equation of line is y – 3x = 0

Now suppose we are having two points as (x_{1}, y_{1}) and (x_{2}, y_{2}) and we are asked to find the equation of the line then we can find the equation of line as

y – y_{1}= m (x – x_{1})

Here the value of m will be = y_{2} – y_{1} /x_{2} – x_{1}

So we can rewrite our line equation as

y – y_{1} = (y_{2} – y_{1} /x_{2} – x_{1}) * (x –x_{1})

if we have two points as (1,2) and (2,3) and we are asked two find the equation of line passing through these points then the equation will be

y – 2 = m (x – 1)

Now we have to find the value of m, so the value of m will be

m = y_{2} – y_{1} /x_{2} – x_{1}

m = 3-2 /2-1

m = 1

Now we will put the value of m in above equation,

y -2 = x -1

y –x =1

This is the required equation of line.

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