Question

in exercises 21-24, determine the number of lines of symmetry for the figure. (see example 5.)
21)
22)
23)
24)

Explanation:

Step1: Analyze trapezoid (21)

A non-isosceles trapezoid has 0 lines of symmetry; this is an isosceles trapezoid, which has 1 vertical line splitting it into mirror halves.

Step2: Analyze cross shape (22)

This shape has 4 lines of symmetry: 2 vertical/horizontal, 2 diagonal, each splitting it into mirror halves.

Step3: Analyze parallelogram (23)

A non-rhombus parallelogram has 0 lines of symmetry, as no line divides it into mirror images.

Step4: Analyze star (24)

This 5-pointed star has 5 lines of symmetry, each passing from a point to the inner indent opposite it.

Answer:

1. 1
2. 4
3. 0
4. 5