1. MATH VOCAB UNIT 3 BY LEXI

2. ACUTE ANGLE Acute Angle- An angle that measures between 0° and 90. 2

3. ADJACENT ANGLE Angles that are next to each other; adjacent angles have a common side, but no other overlap. 3

4. ISOSCELES TRIANGLE A triangle with 2 equal sides. 4

5. CONGRUENT Having the exact same shape or size. 5

6. RADIUS A line segment from the center of a circle (or sphere) to any point on the circle (or sphere) also the length of such a line segment. 6

7. RIGHT ANGLE A 90  angle. 7

8. REFLEX ANGLE An angle that is more then 180  but less than 360 . 8

9. SCALENE TRIANGLE A triangle with all different sides. 9

10. QUADRANGLE A polygon with 4 equal sides. 10

11. TESSELLATION An arrangement of shapes that covers a surface completely without overlaps or gaps also called a tiling. 11

12. OBTUSE ANGLE An angle from 90  to 180 . 12

13. VERTICAL/OPPOSITE ANGLE When two lines intersect, the angles that do not share a common side. Vertical angles have equal measures. 13

14. POLYGON A closed 2-dimensionalfigure that Is made up of line segments joined end to end. The line segments of a may not cross. 14

15. PARALLEL LINES Never meeting always the same distance apart. Lines, line segments, and rays in a plane are parallel if they never meet, no matter how far they are extended. 15

16. STRAIGHT ANGLE A 180  angle. 16

17. EQUILATERAL TRIANGLE A triangle with the same length on all sides. 17

18. REGULAR POLYGON A polygon whose sides are all the same length and whose angles are all equal. 18

19. DIAMETER A line segment that passes through the center of a circle or a sphere and has end points on the circle or sphere also the length of this line segment. The diameter of a circle or sphere is twice the length of radius. 19 See definition for radius slide 6

20. CREDITS 55 th grade math Reference book DDictionary.com GGoogle BBing images 20