Question

a) Verify that PR bisects QS at right angles
b)Verify that QS does not bisect PR
***graph included

Answer 1

10 people asked th exact same question today

Answer 2

and they were in geometry

Answer 3

@Icedragon50 whaaaat really? Where?

Answer 4

here?

Answer 5

ya early today lol

Answer 6

use google

Answer 7

do you have the link to it?

Answer 8

i called u

Answer 9

http://openstudy.com/study#/updates/4dc3a71e3e098b0b19d07cbc

Answer 10

http://www.myinstants.com/search/?name=9%2B10%3D21 its 21 alright

Answer 11

@Icedragon50 WOW 3 YEARS AGOO! yea i saw it but i dont get it....what do i need to find first

Answer 12

lol

Answer 13

so funny

Answer 14

No i don't.
lol idek what connections means...

Answer 15

ohh no i go to real life public school

Answer 16

uhhh whats a brick and motor school now?

Answer 17

well then ask ur teacher lol

Answer 18

its a real public school

Answer 19

she can't teach very well so i need help

Answer 20

:/ ok ima call in some smart people

Answer 21

@dan815

Answer 22

@perl

Answer 23

@nincompoop

Answer 24

http://www.myinstants.com/instant/aint-nobody-got-time/ i agree

Answer 25

lol

Answer 26

@xapproachesinfinity BROTATO IM NOT GOOD IN GEOMETRY

Answer 27

http://www.myinstants.com/instant/badum-tss/ classic

Answer 28

find the coordinates of T
and very that the coordinates are the same using the midpoint

Answer 29

to find a midpoint yo do \[(\frac{x_1+x_2}{2},\frac{y_1+y_2}{2})\]

Answer 30

okay so which points do I plug into the midpoint formula to get T

Answer 31

the end point of the segment QS

Answer 32

points*

Answer 33

b) is basically the same thing. think about it a little bit

Answer 34

okay
m=(x1+x2/2), (y1+y2/2)
=(2+8/2), (8+4/2)
=(10/2), (12/2)
=(5,6)

Answer 35

@xapproachesinfinity ^

Answer 36

PR
m=(x1+x2/2), (y1+y2/2)
=(7+1/2), (9+0/2)
=(8/2), (9/2)
=(4,4.5)

Answer 37

Can someone please tell me if im doing this right?????

Answer 38

@e.mccormick can you please help me with this?

Answer 39

Yes, that finds the midpoint of PR, which is obviously not where they intersect, and therefore QS does not bisect PR. That is the answer for b.

Answer 40

And a little more up... yes again.

Answer 41

Just the reverse...

Answer 42

Okay so both of my solutions were correct then, right?

Answer 43

Well, you found the midpoints. Then you do the comparison and that is the versification (proof) that a is a match and b is not.

Answer 44

So you're saying that there's more to it than visually knowing that (5,6) and (4,4.5) aren't the same...

Answer 45

The right angles part... hmmm, you will need to find the slops of them both.

Answer 46

Okay

Answer 47

Yes and no. You can look at them and say, "They intersect at ..." which may or may not be allowed. However, if you find the equations of the lines you can find where they intersect, which is proof. It depends on how much rigor is needed for a. And, because they want it at right angles, you need the slopes as a minimum.

Answer 48

Oh okay so I need to find the slope of ...QS and PR and make equations for them?

Answer 49

or.. something else

Answer 50

Remember your perpendicular line rule for slope?

Answer 51

negative reciprocal right?

Answer 52

EXACTLY! So you need the slopes to show they are that, which proves they are at right angles.

Answer 53

slope of QS
m=y2-y1/x2-x1
=4-8/8-2
=-4/6
=-2/3
negative recip..... 2/3

Answer 54

It is becaue "a) Verify that PR bisects QS at right angles " has two parts. That it bisects you did by a visual comparison to the found midpoint... now, that can be done more mathematically as well, and it will depend on the teacher if they allow visual or not.

The second part, at right angles, is the whole slope thing.

Answer 55

So all you need is the slope of PR. If it is also 2/3, then that is the right angle proof.

Answer 56

slope of PR
m=y2-y1/x2-x1
=0-9/1-7
=-9/-6
=-3/-2

Answer 57

i can't tell what the negative reciprocal would be

Answer 58

Oops, yah, you made a small mistake in the first thing whjen you said" =-2/3 negative recip..... 2/3" :

\(\dfrac{a}{b}\) has the negative recyprocal of \(-\dfrac{b}{a}\) Get it now?

Answer 59

You swapped the sign, the negative part, but...

Answer 60

so instead of it being 2/3 its -3/2

Answer 61

Oops... you swapped the sign a second time. Just 3/2

Answer 62

okay

Answer 63

i see...

Answer 64

=-2/3 has a negative recip. of 3/2

slope of PR is -3/-2, well, those negatives cancel, so... 3/2

Answer 65

That allows you to use the rule for perpendicular lines and that proves the 90 degree part.

Answer 66

question: how do you find the negative reciprocal is it times -1 or divided by negative 1 of neither?

Answer 67

*or neither

Answer 68

because it seems like there are different rules to everything and then i get confused

Answer 69

Hmmm... technically, mutiply by x to get -1 then sove for x. It is more like a definition than anything else after a certain point.

Answer 70

\(-\dfrac{2}{3}x=-1\)

\(-1\times-\dfrac{2}{3}x=-1\times-1\)

\(\dfrac{2}{3}x=1\)

\(3\times\dfrac{2}{3}x=3\times1\)

\(2x=3\)

\(\dfrac{1}{2}\times2x=\dfrac{1}{2}\times3\)

\(x=\dfrac{3}{2}\)

That would be the mathematical way of finding a negative recyprocal.

Answer 71

Since recyprocals and negatives are both pre-algebrea topics, most algebra classes let you just "know" what they mean.

Answer 72

What do you mean by multiplying x to get -1

Answer 73

What I just did in the example. Where I just used x as my goal.

See, one definition of a recyprocal is the thing you multipy by to get 1. Well, to get the negative recyprocal it is what you need to multiply by to get -1.

Answer 74

Btw I can't see the solution that you've done for some strange reason. I just see codes :/

Answer 75

You have a script blocker? If so, tell it that mathjax.com is OK.

Answer 76

I switched browsers so I can see it now

Answer 77

And I understand it. Thank you!

Answer 78

Good good. =)

So, did you want to know the mathematical way to find the intersection point, are are you going to be OK doing it visually?

Answer 79

Sure!

Answer 80

Well, you kabe the slope and you have points. So you can use the point-slope form to find the equations of the lines. Then solve for the intersection.

Answer 81

have the slope.. bah.

Answer 82

y=mx+b form ?

Answer 83

Yep. You need to find the b, then you have everything for the linear equation.

Answer 84

y=3/2x+b

Answer 85

do i plug in any point?

Answer 86

Well, that is the slope for PR, so one of the PR points.

Answer 87

(1,0) is probably easy.

Answer 88

0=3/2(1)+b
1 1/2=b

Answer 89

y=3/2x+ 1 1/2

Answer 90

Not quite. Forgot something when you moved it from one side to the other.

Answer 91

a=b+c
a-b=b-b+c
a-b=c

Answer 92

oh 1 1/2 turns into a negative

Answer 93

=)

Yep, so PR is on the line y=3/2x-3/2

Answer 94

0=3/2(1)+b
0=1 1/2+b
0-1 1/2=b
-1 1/2=b

Answer 95

Okay:)