See http://prntscr.com/1xbi4y

See Graph a triangle (XYZ) and reflect it over the line y=-x to create triangle X'Y'Z'.

What does, "over the line y = -x," mean.

I know it goes through the origin. But I'm confused. Is there a formula? I have my triangle XYZ. Do I use the formula (x ,y) -- (y, x) to reflect it across y = x? But this says y = -x. I'm confused.

@wio @hartnn

Question

See >> http://prntscr.com/1xbi4y 

See >>>> Graph a triangle (XYZ) and reflect it over the line y=-x to create triangle X'Y'Z'. 


What does, "over the line y = -x," mean. 

I know it goes through the origin. But I'm confused. Is there a formula? I have my triangle XYZ. Do I use the formula (x ,y) -- > (y, x) to reflect it across y = x? But this says y = -x. I'm confused.

@wio @hartnn

anonymous · Answer

Okay since $y=-x$ then solving for $x$ gives $x=-y$
So maybe use the formula: $$
(x,y) \to (-y,-x)
$$

anonymous · Answer

But I'm not completely sure on this actually.

compassionate · Answer

Okay. one second. I did and it reflected from the first quadrant to the third.

anonymous · Answer

|dw:1381777097858:dw|

anonymous · Answer

|dw:1381777130643:dw|
Flipped / reflected across this line