Question

What is the equation of the line that passes through the points (−2, 1) and (1, 10)? 3x − y = −73x − y = −53x − y = 5x + 3y = −5

Answer 1

The two point formula :

$y-y_1=\frac{y_2-y_1}{x_2-x_1}(x-x_1)$

The points are (-2, 1) and (1, 10)

Using the formula above :

$\begin{gathered} y-1=\frac{10-1}{1-(-2)}(x+2) \\ y-1=\frac{9}{3}(x+2) \\ y-1=3(x+2) \\ y-1=3x+6 \\ -3x+y=6+1 \\ -3x+y=7 \\ 3x-y=-7 \end{gathered}$

The answer is 3x - y = -7