Question

One of the triangle s pictured is a rotation of triangles ABC and one of them is a reflection

Answer 1

For a reflection, we have an axis of symmetry. Then, one of the y or x coordinates of the original picture is equal to the corresponding x or y coordinates of the image.

This happens for the red triangle, that is a reflection of ABC over the x-axis: the coordinates of x of the original and image points are the same, while the y-coordinates become negative.

The other image triangle (blue triangle) is a rotation, as the coordinates are transformed as:

`(x,y)\longrightarrow(-y,x)`

Answer:

1. The blue triangle PQR is rotated with center of rotation in the origin.

2. The red triangle XYZ is a reflection over the x-axis.