What is the formula for the midpoint between two points??
$$ (\frac{(x_2 - x_1)}{2}, \frac{(y_2 - y_1)}{2}) $$
What is the formula for the distance between two points??
$$ \sqrt{(y_2 - y_1)^2 + (x_2 - x_1)^2} $$
- Pythagoras
What is the formula for the gradient between two points??
$$ \frac{y_2 - y_1}{x_2 - x_1} = \frac{\text{rise}}{\text{run}} $$
What are the two main ways of expressing the quation of a straight line??
- $y = mx + c$
- $ax + by + c = 0$
When using the $ax+by+c=0$ form of a straight line equation, there is an expectation that…??
$a,b$ & $c$ are integers.
What does it mean if points are collinear??
That the points all lie on a straight line.
What is the “magic” formula for a straight line with unknowns??
$$ y - y_1 = m(x - x_1) $$
What is the formula for a straight line starting $y - y_1$??
$$ y - y_1 = m(x - x_1) $$
How would you subsitute $m = 4$ and $(-2, 1)$ into the magic straight line formula??
$$ y - 1 = 4(x - (-2)) $$
What is the formula for a line with gradient $2$ and passing through $(3, 4)$??
$$ y = 2x - 2 $$
Backlinks
Metadata
date: 2020-09-13 11:00
tags:
- '@?maths'
- '@?school'
- '@?public'
- '@?year-1'
title: Maths - Straight Line Graphs