Question

Which transformations will produce similar, but not congruent, figures?

A) Triangle MNO is reflected across the y-axis and then dilated by a scale factor of 1.8 to form triangle M"N"O".

B) Triangle MNO is reflected across the x-axis and then translated 9 units down to form triangle M"N"O".

C) Triangle MNO is reflected across the x-axis and then rotated 90° clockwise to form triangle M"N"O".

D) Triangle MNO is reflected across the y-axis and then rotated 180° clockwise to form triangle M"N"O".

Answer 1

The one with a dilation

Answer 2

Answer: A) Triangle MNO is reflected across the y-axis and then dilated by a scale factor of 1.8 to form triangle M"N"O".

Explanation:

We know that we prefer rigid motions to create congruent images.

There are four kinds of rigid motions:

1) translation 2) reflection 3) rotation 4) glide reflection.

But a dilation is a transformation that creates an image having similar shape as the original, but with a different size.

So it does not create congruent images.

Hence transformations will produce similar, but not congruent, figures is :

Triangle MNO is reflected across the y-axis and then dilated by a scale factor of 1.8 to form triangle M"N"O".