Coordinate Geometry Flashcards
Distance between points A and B
Squareroot((x2-X1)^2+(y2-y1)^2)
Midpoint of segment AB
(X1+x2)/2 , (y1+y2)/2.
Potential rule for midpoint of the hypotenuse of a right triangle.
All three vertices are equal distance from the midpoint of the hypotenuse of a right triangle.
Parabola
Collection of points in the plane, each of which is equidistance from a fixed line.
Locus
A curve or other figure formed by all the points satisfying a particular equation of the relation between coordinates.
Directrix
A fixed line used to describing a curve or surface. Formula for directrix is y=k-p when graph opens up or down. Formula is x=h-p if the axis opens left or right.
Focus
A fixed point. P=1/4a. Focus formula is (h, k+p) if the parabola opens upward or downward. The formula is (h+p, k) if the directrix opens left or right.
Standard form of a parabola
(Y-k)^2=4p(x-h) the graph opens upward or downward
(X-h)^2=4p(y-k) if the graph opens left or right.
Vertex
A point that is the maximum or minimum of a parabola. It is half the distance from the focus to the directrix.
Ellipse formula
(X-h)^2/(a^2) + (y-k)^2/(b^2)
Hyperbola formula
(X-h)^2/a^2 - (y-k)^2/b^2