Equation of a Line (Leaving Cert Mathematics): Flashcards

$y = mx + c$

Slope of the line

y-intercept (where line crosses y-axis)

$y - y_1 = m(x - x_1)$

A known point on the line

$ax + by + c = 0$

$x = k$ (where $k$ is a constant)

$y = k$ (where $k$ is a constant)

$m = \frac{y_2 - y_1}{x_2 - x_1}$

Slope ($m$) and y-intercept ($c$)

Two points on the line