1. Unit 4 Math Vocabulary By Noah Morisi

2. Acute Angle An acute angle is an angle that measures out less than 90 degrees.

3. Adjacent Angles An Adjacent Angle is an angle, divided into multiple parts, or has another line segment coming from the vertex.

4. Axis An axis is the vertical and horizontal lines that make up the quadrants of a coordinate plane. The vertical axis is usually referred to as the y axis and the horizontal axis is usually referred to as the x axis.

5. Bisecting an angle To bisect an angle is to divide it into 2 congruent parts.

6. Concentric Circles Concentric Circles are circles that have there centers at the same point.

7. Congruent Figures Two figures are congruent if they are the same size and shape - that is, if their corresponding angles and sides are equal.

8. Consecutive Angles Consecutive angles are when two lines are crossed by another line (which is called the Transversal), the pairs of angles on one side of the transversal but inside the two lines are called Consecutive Interior Angles

9. Corresponding angles or sides Corresponding sides and angles are a pair of matching angles or sides that are in the same spot in two different shapes. Look at the pictures below to see what corresponding sides and angles look like

10. Inscribed For something to be inscribed it has to be written, etched, forged into something. Usually its wording or a picture.

11. Isometry Isometry is the transformation of the plane is an isometry if, for all points X and Y, the distance between the image points X' and Y' equals the distance between X and Y. In other words, an isometry is a transformation which preserves distance.

12. Transformation Transformation is the doing of moving a shape so that it is in a different position, but still has the same size, area, angles and line lengths.

13. Line of Reflection The line of reflection is the line in which reflects the shape onto the opposite side, thus creating a “reflection”.

14. Mid Point The mid-point is basically just the exact middle point of something.

15. Obtuse Angle An obtuse angle is an angle that measures to be more than 90 degrees, but less than 180 degrees.

16. Ordered Number Pair An ordered number pair is simply two numbers written in a certain order.

17. Parallel Line A parallel line is a line that in which the line next to it, it will never touch.

18. Perpendicular A line is perpendicular to another if it meets or crosses it at right angles. (90 degrees)

19. Perpendicular Bisector A line which cuts a line segment into two equal parts at 90 degrees.

20. Preimage The preimage is For a point y in the range of a function ƒ, the set of points x in the domain of ƒ for which ƒ(x) = y. For a subset A of the range of a function ƒ, the set of points x in the domain of ƒ for which ƒ(x) is a member of A. Also known as inverse image.

21. Reflection A reflection is simply the reverse of something. Like looking at your REFLECTION in the fountain.

22. Reflex Angle A reflex angle is an angle that is more than 180 degrees.

23. Right Angle A right angle is an angle that measures to be exactly 90 degrees.

24. Rotation A rotation or to rotate something is to turn it, swivel it, or of course, rotate it.

25. Sector The sector is a portion or part of a circle that is closed on both sides.

26. Straight Angle A straight angle is simply an angle that measures out to be exactly 180 degrees. A straight line.

27. Supplementary Angles These two angles (140° and 40°) are Supplementary Angles, because they add up to 180°.

28. Translation Translation means to move a shape with rotating, resizing, or anything else.

29. Transversal A line that crosses across two other lines that are (usually) parallel.

30. Vertex The vertex is the point in which a line segment of an angle meet with another angle.

31. Vertical Angles "Vertical" in this case means they share the same Vertex (corner point), not the usual meaning of up-down