ok so when the coordinate rule looks like this

(x,y)----->(-x,y+5)

what would be the difference between the pre image and the image?

Guest Jun 7, 2019

#1**+3 **

If you take a point and make its x-coordinate negative, that will flip the point over the y-axis.

And if you take a point and add 5 to its y-coordinate, that will shift the point up 5 units.

So the image is the pre-image flipped over the y-axis and shifted up 5 units.

hectictar Jun 7, 2019

#3**+3 **

Another word is "reflected."

For example:

If you take (3, 7) and make its x-coordinate negative, you will get (-3, 7) .

Maybe you can imagine that this graph is an open book where the y-axis is the division between two pages.

If you flipped the page, then the two points would meet.

If you took (3, 7) and flipped it over the y-axis (like flipping the page), you would get (-3, 7) .

So (-3, 7) is (3, 7) flipped over the y-axis.

And you can see that the distance between (3, 7) and the y-axis is the same as the distance between (-3, 7) and the y-axis.

Does that kind of make sense?

hectictar
Jun 7, 2019

#4**+1 **

I like to call it the oppsite of the Number on the cordinate grid say you have (1,-1) well its oppsite is (-1,-1)

or say we have (6,5) well its oppsite or as hectictar had explained how she calls it reflected is (-6,5)

Also to count on a graph you just count each corrdinate across. See because I counted it the to points are 6 corrdinates apart..... Oh yeah thanks hectictar for your image I saved it and did that on it hope your not mad or anything XD

~Nickolas

Nickolas
Jun 7, 2019

#5**+3 **

Nickolas, how would you say that (8, -5) and (8, 5) are related?

What is the opposite of (8, 5) ?

hectictar Jun 7, 2019

#8**0 **

But if you were looking for there oppsites you could flip it over the x axcis instead of the (y) axcis so instead of left or right you could flip going down

Nickolas
Jun 7, 2019

#9**+3 **

Maybe it's a trick question. I was just trying to get you to think.

There isn't a single defined "opposite" of (8, 5) .

Instead of just saying " (8, 5) is the opposite of (-8, 5) " we need to say something like

(8, 5) is the opposite over the y-axis of (-8, 5)

and

(8, 5) is the opposite over the x-axis of (8, -5)

It is important to say which axis that the point is "flipped" over.

hectictar
Jun 7, 2019