Download Acute Angle

Acute Angle
• An angle whose
degree measure
is less than 90.
Noncollinear points
• Points that do not lie on the same
line.
Congruent segments
• Segments that have the same length.
Vertical angles
• Two nonadjacent angles formed by
two intersecting lines.
Collinear points
• Points that lie on the same line.
Adjacent angles
• Two angles in the same plane that
have a common vertex and a
common side, but no common
interior points.
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Straight angle
• A figure formed by two opposite
rays.
Obtuse angle
• An angle with degree measure
greater than 90 and less than 180.
Right angle
• An angle whose degree measure is
90.
Complementary angles
• Two angles whose degree
measures have a sum of 90.
Parallel lines
• Lines in the same plane that do not
intersect.
Coplanar points
• Points that lie in the same plane.
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Base
• The side opposite the vertex angle in
an isosceles triangle.
Base angle
• In an isosceles triangle, the angle
formed by the base and one of the
legs.
Equiangular Triangle
• A triangle with all angles congruent.
Acute Triangle
• A triangle all of whose angles are
acute
Hypotenuse
• In a right triangle, the side opposite
the right angle.
Isosceles Triangle
• A triangle with at least two sides
congruent.
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Equilateral Triangle
• A triangle with all sides congruent.
Obtuse triangle
• A triangle with an obtuse angle.
Skew lines
• Lines that do not intersect and are
not in the same plane.
Vertex angle
• In an isosceles triangle, the angle
formed by the congruent sides.
Scalene Triangle
• A triangle with no two sides
congruent.
Perpendicular lines
• Two lines that intersect to form a
right angle.
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Supplementary angles
• Two angles whose degree measures
have a sum of 180.
Transversal
• A line that intersects two or more
lines in a plane at different points.
Angle bisector of a triangle
• A segment that bisects an angle of
the triangle and has one endpoint at
a vertex of the triangle and the other
endpoint at another point on the
triangle
Opposite rays
• Two rays BA and BC such that B is
between A and C.
Altitude of a Triangle
• A segment from a vertex of the
triangle to the line containing the
opposite side and perpendicular to
the line containing that side
Median of a triangle
• A segment that joins a vertex of the
triangle and the midpoint of the
opposite side.
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Perpendicular bisector of a triangle
Rectangle
• A line or line segment that passes
through the midpoint of a side of a
triangle and is perpendicular to that
side.
• A quadrilateral with four right angles.
Rhombus
• A quadrilateral with four congruent
sides.
Square
• A quadrilateral with four right angles
and four congruent sides.
Trapezoid
• A quadrilateral that has exactly one
pair of parallel sides.
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