Question

The vertices of a triangle are p(-7,-4), Q(-7,-8), and R(3,-3). Name the vertices of the image reflected across the line y=x
p'(4,7), q'(8,-7), r'(3,-3)
p'(4,-7), q'(8,-7), r' (3,3)
p'(-4,-7), q' (8,-7), r'(-3,3)
p'(-4,7), q'(-8,7), r(-3,-3)

Answer 1

@hanner_B_nanner

Answer 2

@iknowit @escapeshipshape

Answer 3

ummmm...hold on just a sec

Answer 4

the rule for reflecting an image across the line y = x is (x, y) → (y, x).
So for P(-7,-4), Q(-7,-8), and R(3,-3) you would just flip them around...

Answer 5

so like (-4,-7), (-8,-7)..

Answer 6

yeah:) but...let me graph it so I can see what the right answer will be...lol

Answer 7

oh okkk :)

Answer 8

the x will be positive and the y will be negative on these when they're reflected.... so it would have to be the last one, I think.

Answer 9

8. Find the image of O(-2,-1) after two reflections, first across the line y=-5, and then across the line x=1
(-2,-1)
(-1,-6)
(4,-9)
(1,-5)

Answer 10

i'm sorry, I'm not sure! Maybe he can help though>>@johnweldon1993

Answer 11

@johnweldon1993 are you good with geometry?

Answer 12

Oh yeah...okay so look at it like this...

"Find the image of O(-2,-1) after two reflections, first across the line y=-5, and then across the line x=1"

So first...when reflecting across y = -5 how far away from -5 is your point?
We are at -1 on the y-axis...and we want to get to -5 ...that is a 4 unit difference right?

So if it takes 4 units to get TO the line...we then need to go 4 MORE units down to make the reflection...

So all together that is -1 - 4 - 4 = - 9 so our new coordinates are (-2, -9)

Now we need to reflect across x = 1

Same thing here...how far away are we (in respect to 'x') to x = 1?

We are at x= -2 ...and we need to get to x = 1....that is a 3 unit difference....we need to go up 3 units to get TO the line...then follow through with another 3 units to complete the reflection....

so

-2 + 3 + 3 = 4

So our entirely new coordinate is (4 , -9)