The lines that contain the altitudes of a triangle are concurrentĀ
Three or more straight lines are said to beĀ āconcurrentāĀ if they all pass through a common point.
This common point is calledĀ āpoint of concurrencyā
The point where the three altitudes meet is the orthocenter theseĀ Ā linesĀ associated with aĀ triangleĀ areĀ concurrentĀ as well.
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