Which of the lines are perpendicular to each other?
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Which of the lines are perpendicular to each other?
Let's remember that perpendicular lines are lines that form a right angle of 90 degrees between them.
In each of the answers, we will draw the letter T at the point of intersection of the lines.
Let's examine figure A:
We will notice that the lines do not form a right angle, and therefore are not perpendicular.
Let's examine figure B:
The lines do indeed form a 90-degree angle and are therefore perpendicular.
Let's examine figure C:
We notice that the lines do not form a right angle, and therefore are not perpendicular.
What do the four figures below have in common?
Look for a perfect square corner where the lines meet! If it looks like the corner of a book or piece of paper, they're likely perpendicular. But always measure to be certain.
All perpendicular lines intersect, but not all intersecting lines are perpendicular! Lines can cross at any angle - only those crossing at exactly 90° are perpendicular.
Not always! You can use the corner test - place a square corner (like from paper) at the intersection. If it matches perfectly on both sides, the lines are perpendicular.
No, perpendicular lines must be straight. Curved lines can meet at right angles at specific points, but we only call straight lines 'perpendicular'.
Extend the lines in your mind or with a ruler! If the extended lines would meet at a 90° angle, then the original line segments are perpendicular.
90 degrees creates the most balanced intersection - it's exactly halfway between parallel (0°) and opposite directions (180°). This creates perfect right angles!
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