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Re: i need help!!!
Posted:
May 30, 2006 4:38 PM


> I am a highschool student taking a geometry class > online and I just want to know
I would not ordinarily respond to a question that just seeks homework help, but these questions are so basic that I'm afraid the student really doesn't understand what's going on. > > > 1.Two lines perpendicular to the same line are > perpendicular to each other. > A. true > B. false Absolutely true in TWO dimensions, absolutely false in THREE dimensions. > 2. All coplanar lines are parallel. > A. true > B. false Coplanar lines lie in one plane. Can't you have two lines lying in one plane which intersect? Like "V" > 3. Any pair of perpendicular lines are coplanar. > A. true > B. false Since any two intersecting lines determine a plane, true. > 4. If two segments are parallel, the lines containing > them are coplanar. > A. true > B. false If the segments are parallel, the lines containing them are parallel (by definition), so they must be coplanar. > 5. Segments which share a common endpoint must be > perpendicular. > A. true > B. false So clearly false. Draw any number of diagrams of 2 intersecting lines forming an obique (nonright) angle. Like the letter V .



