Processes for Median, Altitudes, Perpendicular Bisectors and POIs Flashcards
1
Q
Medians
A
- Calculate midpoint of the relevant line using (x1+x2/2, y1+y2/2)
- Calculate gradient of the line between midpoint and opposite corner using
y2-y1/x2-x1 - Find the equation using this gradient and either of the points (whichever is easier)
2
Q
Altitude
A
- Calculate the gradient of the side which is perpendicular to the altitude using
m=y2-y1/x2-x1 - Calculate the gradient of the altitude using m x m perpendicular = -1 (flip the sign and turn the number inside out ( 5 would go to
- 1/5 for example) - Find the equation using this gradient and the point the altitude passes through using the equation y-b = m(x-a)
3
Q
Perpendicular lines
A
- Calculate the midpoint of the line segment being bisected using M = (x1+x1/2, y1+y2/2)
- Calculate the gradient of the line used used in step 1 using the equation m=y2-y1/x2-x1.
- Using this gradient use the equation m x m perpendicular = -1 (flip the sign and turn the number inside out, -1/3 becomes 3)
- Find the equation of the perpendicular bisector using the point from step 1 and gradient from step 3 inserting into the equation y-b = m(x-a)
4
Q
POIs
A
After finding two of these aforementioned lines put them into a simultaneous equation or use y=y and consequently finding y and x.
5
Q
What is a perpendicular bisector.
A
A line that cuts another line directly in half and at right angles to said line.
6
Q
What is a median?
A
A line that goes from the middle of one line to the corner of another in a triangle.
7
Q
What is an altitude ?
A
A line that goes from the corner of a triangle to cut another line at right angles within the triangle.