Unit 4 Geometry Flashcards
Midpoint formula
X one plus x two Y one plus y two
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2. , 2
Slope formula
Y one minus y two
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X one minus X two
Distance formula
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V ( x one - x two) + ( y one - y two)
Midpoint
Connects the midpoints of the sides of a triangle
Triangle mid segment theorem
The mid segment of a triangle is parallel to one side of the triangle and half the length
Perpendicular bisector theorem
If a point is on the perpendicular bisector line of a triangle then it is equidistant from the endpoint of that segment
Perpendicular bisector theorem converse
If a point of equidistant from the endpoints of a segment then it is the perpendicular bisector of that segment
Angle bisector theorem
If a point is on the bisector of an angle then it is equidistant from the sides of the angle
Angle bisector theorem converse
If a point is equidistant from the sides of and angle then it is on the bisector of the angle
Circumcenter
Point equidistant from all angles of a triangle ( can be outside triangle ) found by drawing perpendicular lines
Incenter
Point equidistant from all three sides of a triangle found by drawing lines from angle bisectors
Centroid
The center of gravity for a triangle also the point where all three medians meet.
Medians
Create the centroid and are are 2/3 of length on one side and 1/3 of length on other side . Also are bisector pf the lines they touch
Altitudes
Perpendicular segment from a vertex of the triangle to the line containing the opposite side also called the height . ( can be inside or outside the triangle )
Orthocenter
The point where 3 altitudes meet can be inside or outside the triangle