Lines Flashcards
1
Q
What is the equation of a line?
A
y-y1=m(x-x1)
Teddy bear eqn
2
Q
How do you work out the gradient of a line?
A
m = y2-y1/x2-x1
3
Q
Steps of how to answer “determine if point (x,y) lies on the line”?
A
Work out gradient
Sub, x, y and m into teddy bear equation
sub x coordinate and y coordinate into equation
if it equals 0 then it does lie on the line
4
Q
What does co-linear mean?
A
Lie on the same line
5
Q
How do you work out the midpoint between two points?
A
Midpoint AB =(x1+x2/2, y1+y2/2)
6
Q
How do you work out the distance between two points?
A
d^2= (x2-x1)^2 + (y2-y1)^2
7
Q
What does it mean if two lines are parallel?
A
They have equal gradients
8
Q
What does it mean if the lines are perpendicular?
A
The gradients are negative reciprocals
When they are multiplied they equal -1
