Answer: You can conclude that the ladder rungs are parallel using the Parallel Transversal Theorem.
Step-by-step explanation: Picture a ladder, all of the rungs are horizontal, but the sides are vertical. So all of the rungs are perpendicular to the sides, making right angles. If all of the rungs make 90 degree angles to the sides, that means that all of the rungs are straight with no angle. This makes sure that the rungs will not hit each other, so they are parallel.
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