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## Integrated math 1

### Course: Integrated math 1>Unit 16

Lesson 5: Proofs with transformations

# Proofs with transformations

## Want to join the conversation?

• At , Sal talks about a bisector. What is a bisector?
• A bisector cuts something evenly in half.
• i understand what the video is saying, but the practice activity that comes next is completely different than the examples in the video, is there something i am missing?
• I had the same problem! I never learned any of the proof laws and rules so I am struggling to understand things like "Vertical angles are complimentary."
• At ~, shouldn't the second multiple choice said "If ∠AOC is rotated...", not "If Ray OA and Ray OC are rotated..."? Because you can't rotate points, rays, lines, or line segments due to them not having a vertex, right?
• Yes, you can rotate those around a point/origin, actually.
• Okay, so I'm going to be the stupid one here...
Even after watching this, I'm still REALLY confused about proofs. I think that they're overwhelming, so that makes it difficult to do my homework. Can someone please help me and explain this a little more? Thank you!
• What is "Theta''s and "Phi's" purpose, and where did the origin of the names come from?
• The names are from Greek: θ, π as I said above. Here, they are used as angle placeholders. Hope this helps!
• why do people use Greek letters for some variables?
• People use greek letters in math because sometimes when you use english letters, you could get confused. So they use greek letters to not get confused.
• Hi, I would really like help with this...I've already completed my geometry course in high school and understood it, but my geometry doesn't do well on standardized tests so I've been taking this course. I just did the practice for proofs with transformations and it seems different from that of the video and rather confusing. I'm not getting it all. Can someone possibly be so kind as to help me? I don't understand the terminology of the practice, and I'm just getting all the answers wrong because I can't understand the questions. I haven't had much of a problem up until now. I'm just hoping for some assistance...
• For a translation, we need to know the vector along which the translation is taking place, something like <4,-2> which says to move 4 units to the right and 2 down. Another way to look at it is along a directed line segment which gives you a distance (directed because it tells which end point to start from and which to end at) and an angle. If we can easily see the change in y and x from the line segment, we do the same as if given a vector.
(1 vote)
• What is "Theta" and "Phi"?
• Greek symbols used for angle placeholders
Theta: θ Phi:φ