Answer: rotation of 180' clockwise about the origin and then dilation with a scale factor of -1, centered at the origin
Step-by-step explanation:
Two triangles are congruent if all the corresponding angles are equal, and if the corresponding side lengths are equal.
Now, this means that if we have a given triangle, and we apply a dilation/contraction, then the resultant triangle will have different side lengths than the initial triangle, then those two triangles can not be congruent.
So we can already discard all the options with dilations.
Now, remember how the dilation works.
If we have a point that is at a distance L of the origin, and we do a dilation of scale factor K centered at the origin, then the new distance of the point and the origin will be K*L.
Notice that if the scale factor is equal to 1, then there is no change.
In the options, we have one where the scale factor is -1.
The minus sign means that will cause the enlargement to appear on the other side of the center of enlargement. But the scale factor still is of absolute value 1, so it will not change anything.
Then the only option that not dilates the triangle is:
Rotation of 180' clockwise about the origin and then dilation with a scale factor of -1, centered at the origin
So this is the only transformation that results in a figure congruent to the triangle ABC
