2. Sample answer: plane ABE 3. A, C B; Sample answer: E 4. D 5. ⃖ ⃗ 6. ⃖SR ⃗ 7. TP ⃗ TS ⃗ TR ⃗ TQ ⃗ ; TP ⃗ and TQ ⃗ are opposite rays; TR ⃗ and TS ⃗ are opposite rays 8. Sample answer: T R P S Q j k M N 9. Sample answer: A B C 10. Sample answer: k M 1.2 Explorations 1. a. Check students’ work. b. 4 —4 5 2. Maths in the broad sense of the word is a peculiar form of the general process of human knowledge of the real world. 3. Maths deals with the space forms and quantity relations abstracted from the physical world.The big idea is to allow students to play with some math ideas in a context they can relate to, then bring in the procedure and using their thinking and ideas, help them see the connections. There are times in Algebra the context is a little hazy for me.