Write the equation of the line passing through the points (0, -4) and (-2, 2).

Question

anonymous · Answer

Find slope.
$$m = \frac{ y2 - y1 }{ x2 - x1 }$$$$m = \frac{ 2 - (-4) }{ -2 - 0 } = \frac{ 2 + 4 }{ -2 - 0 } = \frac{ 6 }{ -2 } = -3$$Slope is -3.


You have the slope(-3) and you have a given point (0, -4).
Point-Slope form.
y - y1 = m(x - x1)

m is slope
Substitute the x- and y-values of your point, for x1 and y1.

So you have:$$y - (-4) = -3(x - 0)$$or$$y + 4 = -3(x - 0)$$
Change into Slope-Intercept form.
y = mx + b
$$y + 4 = -3(x - 0)$$Distribute. $$y + 4 = -3x - 0$$Solve for y. 
Subtract 4 from both sides.$$y = -3x - 4$$^---There is your equation.

anonymous · Answer

Hopefully this helped you understand the concept! (: