TRANSVERSAL VOCABULARY

TRANSVERSAL a line that crosses at least two other lines

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

PERPENDICULAR LINES Lines that are at right angles (90°) to each other.

ACUTE ANGLE An angle less than 90º

OBTUSE ANGLE An angle that is more than 90° but less than 180°

RIGHT ANGLE An angle which is equal to 90°, one quarter of a full revolution.

COMPLEMENTARY ANGLES Two angles that add up to 90 degrees (a Right Angle). They don't have to be next to each other, just so long as the total is 90 degrees.

STRAIGHT ANGLE An angle that measures 180º, a straight line

SUPPLEMENTARY ANGLES Two angles add up to 180 degrees. They don't have to be next to each other, just so long as the total is 180 degrees.

VERTICAL ANGLES Vertical Angles are the angles opposite each other when two lines cross. They are always equal.

ADJACENT ANGLES Two angles that have a common side and a common vertex (corner point), and don't overlap.

CORRESPONDING ANGLES Angles in matching corners of a transversal are called corresponding angles.

INTERIOR ANGLES An angle inside a shape or transversal

EXTERIOR ANGLES An angle on the outside of parallel lines that are crossed by a transversal

ALTERNATE INTERIOR ANGLES The pairs of angles within a transversal that are • on opposite sides of the transversal  • but inside the two lines  These angles are equivalent

ALTERNATE EXTERIOR ANGLES The pairs of angles within a transversal that are • on opposite sides of the transversal  • but outside the two lines  These angles are equivalent

CONSECUTIVE ANGLES The pairs of angles within a transversal that are • on SAME sides of the transversal  • but NEXT to each other. These angles add up to 180º