**Geometry** (Ancient Greek: *γεωμετρία*; *geo-* "earth", *-metron* "measurement") is a branch of mathematics concerned with questions of shape, size, relative position of figures, and the properties of space. A mathematician who works in the field of geometry is called a geometer. Geometry arose independently in a number of early cultures as a body of practical knowledge concerning lengths, areas, and volumes, with elements of a formal mathematical science emerging in the West as early as Thales (6th Century BC). By the 3rd century BC geometry was put into an axiomatic form by Euclid, whose treatment—Euclidean geometry—set a standard for many centuries to follow. Archimedes developed ingenious techniques for calculating areas and volumes, in many ways anticipating modern integral calculus. The field of astronomy, especially mapping the positions of the stars and planets on the celestial sphere and describing the relationship between movements of celestial bodies, served as an important source of geometric problems during the next one and a half millennia. Both geometry and astronomy were considered in the classical world to be part of the Quadrivium, a subset of the seven liberal arts considered essential for a free citizen to master.

The introduction of coordinates by René Descartes and the concurrent developments of algebra marked a new stage for geometry, since geometric figures, such as plane curves, could now be represented analytically, i.e., with functions and equations. This played a key role in the emergence of infinitesimal calculus in the 17th century. Furthermore, the theory of perspective showed that there is more to geometry than just the metric properties of figures: perspective is the origin of projective geometry. The subject of geometry was further enriched by the study of intrinsic structure of geometric objects that originated with Euler and Gauss and led to the creation of topology and differential geometry.

In geometry, a **transversal plane** is a plane that intersects (not contains) two or more lines or planes. A transversal plane may also form dihedral angles.

Transversal plane theorem for lines: Lines that intersect a transversal plane are parallel if and only if their alternate interior angles formed by the points of intersection are congruent.

- A transversal that is perpendicular to two parallel lines forms ____ congruent angles?
- When two parallel lines are cut by a transversal how many pairs of corresponding angles are formed?
- If two parallel lines are cut by a transveral, are the corresponding angles congruent?
- Complete the statement. If a transversal intersects two parallel lines, then angles are supplementary?
- To whom Two parallel lines are cut by a transversal. Find the measure of the angle if a pair of interior angles on the same side of the transversal are represent?
- If a transversal intersects two parallel lines then angles are supplementary?
- If two lines are cut by a transversal so that corresponding angles are congruent, then the lines are?
- If two lines are cut by a transversal so that corresponding angles are consistent the lines are what?

- What Are Parallel Lines Cut By Transversal Called at AskivesWhat Are Parallel Lines Cut By Transversal Called? ... If two parallel lines are intersected by a transversal, then the corresponding angles are congruent.