1. Unit 3 math vocabulary Definitions and examples by Tatum

2. Acute angle  An acute angle is a positive angle that measures less than 90 degrees.

3. Adjacent angle  An adjacent angle is a positive angle that measures less than 90 degrees.

4. Isosceles triangle  An isosceles triangle is a triangle with at least two equal sides.

5. 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.

6. 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.

7. Right angle  A right angle is an angle whose measure is 90 degrees.

8. Reflex angle  A reflex angle is an angle that is more that 180 degrees and less that 360 degrees.

9. Scalene triangle  A scalene triangle is a triangle with three unequal sides.

10. Quadrangle  A quadrangle is a polygon with four sides.

11. 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.

12. Obtuse angle  An obtuse angle is an angle whose measure is greater than 90 degrees.

13. 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.

14. Polygon  A polygon is the union of several line segments that are joined together so as to completely enclose an area.

15. Parallel lines  A parallel line is two lines that are in the same plane and never intersect.

16. Straight angle  A straight angle is an angle that measures 180 degrees.

17. Equilateral triangle  An equilateral triangle is a triangle that has three equal sides.

18. Regular polygon  A regular polygon is a polygon in which all the angles are equal and all of the sides are equal.

19. Diameter  Diameter is the line segment joining two points on a circle and passing through the center.