Unit 9 Retest

Front

What are the coordinates of a point after a rotation of 180° clockwise around the origin?

Back

To find the new coordinates after a 180° rotation, negate both the x and y coordinates of the original point. For example, if the original point is (x, y), the new coordinates will be (-x, -y).

Front

What is reflection over the x-axis?

Back

Reflection over the x-axis means that for any point (x, y), the new point after reflection will be (x, -y).

Front

What is reflection over the y-axis?

Back

Reflection over the y-axis means that for any point (x, y), the new point after reflection will be (-x, y).

Front

What is rotational symmetry?

Back

A shape has rotational symmetry if it can be rotated around a central point and still look the same at certain angles. For example, a circle has infinite rotational symmetry.

Front

What is the scale factor in dilation?

Back

The scale factor is a number that scales, or multiplies, the dimensions of a shape. A scale factor greater than 1 enlarges the shape, while a scale factor between 0 and 1 reduces it.

Front

How do you dilate a point by a scale factor?

Back

To dilate a point (x, y) by a scale factor k, multiply both coordinates by k. The new point will be (kx, ky).

Front

What is the effect of a 180° rotation on the coordinates (3, 2)?

Back

The new coordinates after a 180° rotation will be (-3, -2).

Front

What is the effect of reflecting the point (4, -5) over the x-axis?

Back

The new coordinates after reflection over the x-axis will be (4, 5).

Front

What is the effect of reflecting the point (-3, 7) over the y-axis?

Back

The new coordinates after reflection over the y-axis will be (3, 7).

Front

Which letters have rotational symmetry?

Back

Letters like 'N', 'S', and 'Z' have rotational symmetry, as they look the same when rotated 180°.