https://static.k12.com/nextgen_media/assets/8074848-NG_GMT_A_02_U01_Quiz_DP024_102_001_prompt.jpg Which lines are parallel in the square pyramid? Select each correct answer. A. BC←→ and DE←→ B. AD←→ and BC←→ C. AB←→ and AD←→ D. CD←→ and BE←→
@Vocaloid
Parallel=lines that never intersect
the arrows is on the top
any ideas? for example, just test the answer choices one by one: are BC and DE parallel? check the original picture
yes
good, so A is one possibility what about choice B? are AD and BC parallel?
no
good, so eliminate B what about choice C? are AB and AD parallel?
no
good, what about choice D? are CD and BE parallel?
yes
good so A&D are your solutions
https://static.k12.com/nextgen_media/assets/1541442-IM1_141006_050213.jpg The figure shown is a rectangular prism. Which edges are parallel to AH¯¯¯¯¯¯ ? Select each correct answer. A. PA¯¯¯¯¯ B. BD¯¯¯¯¯ C. DK¯¯¯¯¯¯ D. BM¯¯¯¯¯¯ E. MK¯¯¯¯¯¯¯
the lines are on top
well let's try drawing them out |dw:1533917051213:dw|
|dw:1533917062876:dw| all the lines parallel to AH are marked in red - which choices correspond?
BD, PA, MK
hm not quite, PA is this side so it's not parallel|dw:1533917197978:dw| but BD + MK = your solutions
BD and MK are my only solutions
yup the others are perpendicular
https://static.k12.com/nextgen_media/assets/1541443-IM1_141006_050214.jpg The figure shown is a rectangular prism. Which edges are perpendicular to PR¯¯¯¯¯ ? Select each correct answer. A. QT¯¯¯¯¯ B. TJ¯¯¯¯¯ C. HP¯¯¯¯¯¯ D. TR¯¯¯¯¯ E. RA¯¯¯¯¯
similar logic as last time but we want all the perpendicular edges |dw:1533917381802:dw|
|dw:1533917387690:dw|
actually I missed one, include TR
QT, HP, TR
hm not quite, QT is parallel not perpendicular
notice how RA is also perpendicular to PR so it's every choice except QT
https://static.k12.com/nextgen_media/assets/1541446-IM1_141006_050217.jpg Rodrigo knows that AM←→−⊥MN←→− and UK←→⊥MN←→− . What other facts can Rodrigo conclude are true? Select each correct answer. A. AL←→∥UK←→ B. AL←→⊥LT←→ C. MN←→−∥LT←→ D. m∠MBK = 90°
by the way with the other question it's every choice but that doesn't include QT ?
yes
well let's go one by one AM is perp. to MN UK is perp. to MN there's a theorem that states: if two lines (let's call them A and B) are both perpendicular to the same line (let's call it C) then A + B are parallel making statement 1 true
however we don't know anything about LT (it "looks" perpendicular but there's no evidence such as angle measurements or markings to show that LT is parallel to anything) eliminating choices B +C
as for choice D: <MBK is the angle across from UBN, and UBN is 90 degrees so is <MBK also 90 degrees? remember the definition of vertical angles
it is
good so A+D are your solution
yikes let's go through them one by one look at lines AB + CD. they both are perpendicular to the same line, so using the logic from before are AB and CD parallel, perpendicular, or neither?
they look perpendicular
to me
|dw:1533918271489:dw|
|dw:1533918276763:dw|
notice how AB and BC are both perpendicular to GH which, by our earlier problem, means that AB and BC are ~parallel~ to each other
** AB and CD are parallel
ok
using the same logic, AB and EF are also parallel since they're perpendicular to the same line so so far we have the first two choices selected
AB and CD, and AB and EF are parallel
correct ?
good
now, let's look at IK and KL. they don't give us any angle information or any markings to show parallel and perpendicular so we can't determine anything about them
last one, CD and GH - take a look at the diagram and notice how there's a 90 degree angle between them - does that make them parallel or perpendicular?
perpendicular
awesome so the first two choices are parallel, the third choice is "cannot be determined" and the last choice is perpendicular ~
anyway I need to make lunch for my family, if you have any urgent questions you might be able to ask shadow if he can assist
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