Transversal of parallel lines

A transversal is a line that intersects two other lines.

Two angles formed by a transversal crossing two lines are corresponding angles if they are in matching corners.

Two angles are supplementary angles if their measures add up to 180°.

∠ABD and ∠DBC are supplementary angles.

Learn with an example

Check each pair of angles.

∠OPM and ∠LMP are not corresponding angles. They are not in matching corners.

∠OPM and ∠LMK are corresponding angles. They are in matching corners.

∠OPM and ∠OPR are not corresponding angles. They are not in matching corners.


∠OPM and ∠NMP are not corresponding angles. They are not in matching corners.

First find ∠FEH.

Check each pair of angles.

∠FEH and ∠DEH are supplementary angles. Their measures add up to 180°.

∠FEH and ∠DEC are not supplementary angles. Their measures do not add up to 180°.

∠FEH and ∠GHE are not supplementary angles. Their measures do not add up to 180°.

∠FEH and∠ IHJ are not supplementary angles. Their measures do not add up to 180°.

First find ∠LKH.

Check each pair of angles.

∠LKH and∠ LKM are supplementary angles. Their measures add up to 180°.

∠LKH and ∠JKM are not supplementary angles. Their measures do not add up to 180°.

∠LKH and ∠GHK are not supplementary angles. Their measures do not add up to 180°.

∠LKH and ∠IHF are not supplementary angles. Their measures do not add up to 180°.

let’s practice!