Lines of Symmetry & Dilations

Front

What is a line of symmetry?

Back

A line of symmetry is a line that divides a shape into two identical parts that are mirror images of each other.

Front

What does dilation mean in geometry?

Back

Dilation is a transformation that alters the size of a figure but keeps its shape, using a scale factor.

Front

What is a scale factor?

Back

A scale factor is a number that scales, or multiplies, the dimensions of a shape during a dilation.

Front

If a shape is dilated by a scale factor of 1/2, what happens to its size?

Back

The shape is reduced to half its original size.

Front

What are the coordinates of a point (x, y) after a dilation with a scale factor of k?

Back

The new coordinates will be (kx, ky).

Front

What is the effect of a negative scale factor on a shape?

Back

A negative scale factor not only changes the size but also reflects the shape across the origin.

Front

How do you find the image of a point under dilation?

Back

Multiply the coordinates of the point by the scale factor.

Front

What is the difference between enlargement and reduction in dilation?

Back

Enlargement increases the size of a shape (scale factor > 1), while reduction decreases the size (scale factor < 1).

Front

Can a dilation be both an enlargement and a reduction?

Back

Yes, depending on the scale factor used.

Front

What is the center of dilation?

Back

The center of dilation is the fixed point in the plane about which all points are expanded or contracted.