Unit 3 math vocabularyDefinitions and examples by Tatum

Acute angle An acute angle is a positive angle

that measures less than 90 degrees.

Adjacent angle An adjacent angle is a positive angle

that measures less than 90 degrees.

Isosceles triangle An isosceles triangle is a triangle with

at least two equal sides.

Congruent Something that is congruent are

shapes or angles are congruent if you could put one on top of the other, and they would look like just one shape. Equal.

Radius Radius is the distance from the

center to a point on a circle.   The line segment from the center to a point on a circle.

Right angle A right angle is an angle whose

measure is 90 degrees.

Reflex angle A reflex angle is an angle that is more

that 180 degrees and less that 360 degrees.

Scalene triangle A scalene triangle is a triangle with

three unequal sides.

Quadrangle A quadrangle is a polygon with four

sides.

Tessellation A pattern that tessellates is basically, a

tessellation is a way to tile a floor (that goes on forever) with shapes so that there is no overlapping and no gaps.

Obtuse angle An obtuse angle is an angle whose

measure is greater than 90 degrees.

Opposite angle A Opposite angle is when two lines

intersect, four angles are formed. The angles that are directly opposite to each other are called Opposite Angles.

Polygon A polygon is the union of several line

segments that are joined together so as to completely enclose an area.

Parallel lines A parallel line is two lines that are in

the same plane and never intersect.

Straight angle A straight angle is an angle that

measures 180 degrees.

Equilateral triangle An equilateral triangle is a triangle

that has three equal sides.

Regular polygon A regular polygon is a polygon in

which all the angles are equal and all of the sides are equal.

Diameter Diameter is the line segment joining

two points on a circle and passing through the center.