Question

Write an equation of the line that passes through (2,-4) and (0,-4)

Answer 1

y = mx + b

To find the slope(m), you use the slope formula:

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

You plug in the points into the equation.

$m = \frac{-4 - (-4)}{0 - 2}$

$m = \frac{-4+4}{0-2} = \frac{0}{-2} =0$

The slope is 0

y = 0x + b

Any number multiplied by 0 is 0. So:

y = b

To find b, you plug in the y value of either of the points.

-4 = b

Your equation is:

y = -4 (This is a horizontal line)