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How do I reflect x=1 on this shape? The coordinates are (2,-8), (3,-4), and (9,-6). All are listed in order.

April 24, 2014

15 Comments • Newest first

katywashere

[quote=AllConditions]lmao what was the point of this post? does it make you feel good that you can act all smart and tell him off like hes some lazy poop (maybe he is)
man people like you are ri dic u lous
freal

man original poster just listen to these helpful people and do your thang
id answer but these homies got my back and they answered for you cause they want my love and attention
your welcome[/quote]

Guuurl you preach dat

Reply April 25, 2014
LowWillpower

If you want to think of it non-visually (using the magic of algebra and math!):

say we are given a line of reflection x = n and one set of coordinates (a,b) (since any more than one set is just repeating this for that set)

The distance in the x direction from the line of reflection to the coordinate is (a - n). It must go this distance on the opposite side of the line of reflection, therefore the new coordinate must be at x = (n - (a - n)) = (2n - a), so your coordinate (a , b) => (2n - a, b)

This will work for any x axis line of reflection at point n.

If the line of reflection is in the y-axis y = m, you can do the same thing to find that (a , b) => (a , 2m - b)

For this question (since people already solved) that gives us n = 1, therefore new x coordinates are (2 - 2, 8); (2 - 3, -4); (2-9, -6) => (0 , -8);(-1, -4);(-7, -6)

@9Hades9: That doesn't work.

Reply April 25, 2014 - edited
TheGeoffPB

You should have said, "How do I reflect this shape across x=1?" The way you worded it made me think you were trying to reflect the line across the the triangle.

Reply April 24, 2014 - edited
9Hades9

Let x0 = 1
For each point(x,y) do:
reflected point = (x0-x, y)

Draw all the points and connect the right edges.

Reply April 24, 2014 - edited
thewarrioir21

[quote=ehnogi]Here is a better way to visualize this concept:

Get graph paper.
Draw x and y axis and number them.

Draw dots here:

(2,-8), (3,-4), and (9,-6)

Fold the paper vertically at x = 1.
On the right side of the fold, you'll have your dots, and on the left side you'll have the other side without any dots.
When you fold your paper, the dots will touch the blank side of the paper.
Wherever the dots touch, are where your "reflected" points are.[/quote]

lol why did i not think of this before

Reply April 24, 2014 - edited
AllConditions

[quote=Yumtoast]lmao what was the point of this post? does it make you feel good that you can act like an idiot? freal

But on a more serious note: no, it's because there's a huge difference between asking for HW help, and asking for someone to solve the problem without putting any effort into it. Not to mention that HW threads don't generate discussion; if you forgot, a forum's purpose is for discussion and not one-sided fishing.[/quote]

Totally agree with you, but the guy already had it answered so I thought to this post to be quite redundant.
I'm probably more frustrated than others about this sort of thing most probably because a bunch of idiots will post the most irrelevant posts whenever I happen to open up a thread

Reply April 24, 2014 - edited
ehnogi

Here is a better way to visualize this concept:

Get graph paper.
Draw x and y axis and number them.

Draw dots here:

(2,-8), (3,-4), and (9,-6)

Fold the paper vertically at x = 1.
On the right side of the fold, you'll have your dots, and on the left side you'll have the other side without any dots.
When you fold your paper, the dots will touch the blank side of the paper.
Wherever the dots touch, are where your "reflected" points are.

Reply April 24, 2014 - edited
Yumtoast

[quote=AllConditions]lmao what was the point of this post? does it make you feel good that you can act all smart and tell him off like hes some lazy poop (maybe he is)
man people like you are ri dic u lous
freal[/quote]
lmao what was the point of this post? does it make you feel good that you can act like an idiot? freal

But on a more serious note: no, it's because there's a huge difference between asking for HW help, and asking for someone to solve the problem without putting any effort into it. Not to mention that HW threads don't generate discussion; if you forgot, a forum's purpose is for discussion and not one-sided fishing.

Reply April 24, 2014 - edited
AllConditions

[quote=Yumtoast]This is grade school material, so it should be expected that you'll get grade-school answers.

You didn't even make an attempt at the problem before posting.[/quote]

lmao what was the point of this post? does it make you feel good that you can act all smart and tell him off like hes some lazy poop (maybe he is)
man people like you are ri dic u lous
freal

man original poster just listen to these helpful people and do your thang
id answer but these homies got my back and they answered for you cause they want my love and attention
your welcome

Reply April 24, 2014 - edited
DrHye

Craftinrock is right. The general method is that you count the distance from each point to the line of reflection, then count it again in the other direction starting at the line, and plot the point.

http://www.regentsprep.org/Regents/math/geometry/GT1/reflect.htm

The notations they use might be kind of confusing if you haven't seen them in class before, but scroll down to the bottom for "Reflecting over any line"

Reply April 24, 2014 - edited
Yumtoast

[quote=thewarrioir21]Thx for not helping![/quote]
This is grade school material, so it should be expected that you'll get grade-school answers.

You didn't even make an attempt at the problem before posting.

Reply April 24, 2014 - edited
mitarumetaro

refer to above post

Reply April 24, 2014 - edited
hgvd

refer to abov post.

Reply April 24, 2014 - edited
thewarrioir21

[quote=mitarumetaro]With a mirror
Next question.[/quote]
Thx for not helping!

Reply April 24, 2014 - edited
mitarumetaro

With a mirror
Next question.

Reply April 24, 2014 - edited