Question

Which figure represents the image of parallelogram LMNP after a reflection across the line y = x? (see image)

Answer 1

When you reflect a point across the line y = x, the x-coordinate and y-coordinate change places. This gives you such reflection rule:

$(x,y)\rightarrow (y,x).$

From the diagram:

L(3,1), M(4,3), N(5,3) and P(4,1).

Using the reflection rule, you can find coordinates of image points:

L'(1,3), M'(3,4), N'(3,5) and P'(1,4).

As you can see, these are coordinates of vertices of the figure C.

Answer: correct choice is option 3 - figure C.

Answer 2

The answer is figure C. Good luck!