Basic Coordinate Geometry (Edexcel A-Level Mathematics): Flashcards

Two perpendicular axes: $x$-axis and $y$-axis.

By an ordered pair $(x, y)$.

Distance = $\sqrt{(x_2 - x_1)^2 + (y_2 - y_1)^2}$

Midpoint = $((x_1 + x_2)/2, (y_1 + y_2)/2)$

$m = (y_2 - y_1) / (x_2 - x_1)$

The line rises from left to right.

$y = mx + c$

They have the same slope, $m_1 = m_2$.

$m_1 \times m_2 = -1$

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