Question

the backdrop will be supported by two perpendicular supports, as shown in the image.
which definition best describes what it means for lines ab and cd to be perpendicular?
ab is perpendicular to line cd if ab and cd intersect at a 45 - degree angle.
line ab is perpendicular to line cd if ab and cd intersect to form supplementary angles.
line ab is perpendicular to line cd if their intersection forms a right angle.
line ab is perpendicular to line cd if the measure of \\( \angle aoc \\) equals the measure of \\( \angle aob \\).

Explanation:

• Perpendicular lines are defined as lines that intersect at a right angle (90 - degree angle).
• A 45 - degree angle is not a right angle, so the first option is incorrect.
• Supplementary angles add up to 180 degrees. Intersecting lines always form supplementary angles (adjacent angles), but this does not define perpendicularity.
• If the measure of ∠AOC equals the measure of ∠AOB, it does not imply a right - angle relationship.

Answer:

Line \(AB\) is perpendicular to line \(CD\) if their intersection forms a right angle.