Parallel-Transversal Angle Relationships

Before this, knowParallel Lines Create Congruent Angles

Illustrated · 1 min

So parallel lines and transversals. When a tranversal intersects two parallel lines, 8 angles are formed. There are 4 types of angles formed. One is corresponding angles, angles on the same side of the transversal, but are not adjacent or both exterior/ both interior. One must be exterior and the other interior for the angles to be corresponding. In parallel lines, these two angles will be congruent. Another pair of angles formed is alternate interior. There are the angles within the parallel lines, but are on opposite sides of the transversal. In parallel lines, these angles will also be congruent. Another is consecutive interior angles. These are angles within the parallel lines, but are also on the same side of the transversal. These angles will be supplementary in parallel lines. The final types of angles formed are the alternate exterior angles. These are angles formed on the outside of the parallel lines, that are on opposite sides of the transversal. These will be congruent in parallel lines.

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