Reagan’s unit 5 math vocab By: Reagan M

Acute angle An acute angle is an angle that measures less then 90 degrees.

Adjacent angles An adjacent angle is two angles that share the same vertex and sides but do not intersect.

Axis An axis are the lines that go vertical and horiztioal on a coorection grid, the axis are called y and x.

Bisecting an angle Bisecting an angle is when you divide an angle into two part, usually two even parts.

Concentric circle Two or more circles which have the same center point

Congruent figure Figures that have exactly the same shape ad size are said to be congruent to each other.

Consecutive angles Angles that occur one right after the other. Consecutive angles are on either end of the same line segment in a polygon.

Corresponding angles or sides Two angles that are located in the same relative location. If a transversal intersects two parallel lines, corresponding angles appear on the same side of the transversal.

Inscribed To draw on the inside of, touching as many points as possible.

Isometry An isometry is a transformation in which the original figure and its image are congruent.

Line of reflection The line of reflection is the perpendicular bisector of the segment joining every point and its image.

Midpoint A point on a line segment that divides it into two equal parts

Obtuse angle An obtuse angle is more than 90° but less than 180°

Ordered numbered pair Two numbers written in a certain order

Parallel Lines Two lines on a plane that never meet. They are always the same distance apart.

Perpendicular A line is perpendicular to another if it meets or crosses it at right angles

Perpendicular bisector Perpendicular Bisector is a perpendicular line or a segment that passes through the midpoint of a line.

Preimage The original figure before transformation

Reflection A transformation in which a geometric figure is reflected across a line, creating a mirror image.

Reflex angle A Reflex Angle is an angle which is more than 180° but less than 360°

Right angle An angle with a measure of 90 degrees

Rotation The distance from the center to any point on the shape stays the same.

Sector A "pie-slice" part of a circle - the area between two radiuses and the connecting arc of a circle.

Straight angle An angle that has a measure of 180 degrees and is half of 360 degrees

Transformation A transformation is a general term for four specific ways to manipulate the shape of a point, a line, or shape. The original shape of the object is called the pre-image and the final shape and position of the object is the image under the transformation.

Translation A transformation is a general term for four specific ways to manipulate the shape of a point, a line, or shape. The original shape of the object is called the pre-image and the final shape and position of the object is the image under the transformation.

Transversal A line that crosses at least two other lines

Vertex A point where two or more straight lines meet. A corner.

Vertical angles Vertical Angles are the angles opposite each other when two lines cross.