Geometry always, sometimes, never
Always
If points C, D, and E are not collinear, then point C and line AB define a unique plane
Sometimes
If two sides of one triangle are proportional to two sides of another triangle, the triangles are similar
sometimes
Opposite sides of a trapezoid are parallel
always
two intersecting lines form a plane
sometimes
two lines that never intersect are parallel lines
Always
Two isosceles triangles are similar to an equilateral triangle
Always
Two planes that are perpendicular to the same plane are perpendicular to each other
Always
Two right triangles are similar if both legs of one are proportional to the legs of the other
Never
a parallelogram has both pairs of opposite angles supplementary
sometimes
a quadrilateral with diagonals that are perpendicular bisectors of each other is a square
always
as the number of sides of a regular polygon increases, the measure of each exterior angle decreases
always
if a parallelogram has one right angle then it is a rectangle
always
the diagonals of a square are congruent
Never
the diagonals of a trapezoid bisect each other
Never
the intersection of two planes is a point
