Question

Find the equation of the line that would go through point (9,-1) and (-4.25,-1)

Answer 1

Given: The two points below

$\begin{gathered} Point1:(9,-1) \\ Point2:(-4.25,-1) \end{gathered}$

To Determine: The equation of the line that passes through that points

Solution

The formula for finding the equation of a line that passes through two points is

$\begin{gathered} Point1:(x_1,y_1) \\ Point2:(x_2,y_2) \\ Equation \\ \frac{y-y_1}{x-x_1}=\frac{y_2-y_1}{x_2-x_1} \end{gathered}$

Let us substitute the given into the formula

$\begin{gathered} \frac{y--1}{x-9}=\frac{-1--1}{-4.25-9} \\ \frac{y+1}{x-9}=\frac{-1+1}{-13.25} \\ \frac{y+1}{x-9}=\frac{0}{-13.25} \\ \frac{y+1}{x-9}=0 \\ y+1=0 \\ y=-1 \end{gathered}$

Hence, the equation of the line is y = -1