If a right line (EF) intersect two parallel right lines (AB, CD), it makes:
- the alternate angles (AGH, GHD) equal to one another;
- the exterior angle (EGB) equal to the corresponding interior angle (GHD);
- the two interior angles (BGH, GHD) on the same side equal to two right angles.
If a right line (EF) intersect two parallel right lines (AB, CD), it makes:
- the alternate angles (AGH, GHD) equal to one another;
- the exterior angle (EGB) equal to the corresponding interior angle (GHD);
- the two interior angles (BGH, GHD) on the same side equal to two right angles.