Midpoint of AB= (x1+x2/2, y1+y2/2)
The distance AB= (root)(x2-x1)sqr+(y2-y1)sqr (pythagoras)
A=(7, -10) B=(4, -8)
Find the midpoint
Find the length of line AB.
The gradient of AB is y1-y2/x1-x2
If two lines have the same gradient, they are parallel
two lines are perpendicular if the angle between them is 90deg.
the product of these lines are -1
A= (6,7) B=(5,-4)
Find the gradient.
Find the gradient of the line perpendicular to this line.
The equation of a straight line is y=mx+c
m is the gradient and c is the y-intercept
Another equation of a straight line is y-y1=m(x-x1)
Find the equation of the line through the points A and B
A is at (3,2) and B is at (6,11)
A is at (-1,2) and B is at (1,12)
A is at (-5,-3) and B is at (4,1)
use simultaneous equations to find the point where these two lines intersect:
if there are two y= or x=, put both equations equal each other.
If there is just one question with 1 y or x=, replace the y or x in the other equation with the equation y or x=.
The edges of triangle ABC are given by the equations:
Find the coordinates of vertices A, B and C.
Start with a sketch
choose a pair of equations and solve simultaneously