Name: Class: Student ID:

1. Fill in the blanks.

1. If a graph is folded in half along a straight line, the graphs on both sides can completely overlap. This graph is (axisymmetric graph), and the straight line where the crease is located is called (symmetrical axis).

2. In a symmetrical figure, the opposite points on both sides of the axis of symmetry are symmetrical (the distance is equal, and the connecting line of the opposite points on both sides is perpendicular to the axis of symmetry).

Second, judge.

1. The straight line passing through the center of the circle is the symmetry axis of this circle. ( √ )

2. A circle is an axisymmetric figure, and each diameter is its axis of symmetry. ( √ )

3. The isosceles trapezoid is a symmetrical figure. ( √ )

A square has only one axis of symmetry. ( ╳ )

Three. choose

1.4, and the number of symmetry axes in the following figure is the largest (H.)

A. square B. rectangle C. isosceles triangle D. isosceles trapezoid

E. equilateral triangle F. angle G. line segment H. circle I. regular pentagram

2. The following is not an axisymmetric figure (②).

① Rectangle ② Parallelogram ③ Circle ④ Semicircle

3. A puppy is enjoying his full-length portrait in front of a flat mirror (pictured). At this time, he saw (a).

4.(2004? Anhui) as shown in figure 14- 18, among the following patterns, (c) is an axisymmetric figure.

A.( 1)(2)b .( 1)(3)c .( 1)(4)d .(2)(3)

5.(2004? Xiamen) as shown in figure 14- 19, in the following patterns, the axis symmetry is (B.)

Figure 14- 19

A.( 1)(2)b .( 1)(3)(4)c .(2)(3)d .( 1)(4)

6, the following English letters belong to the axisymmetric figure is (D)

USA, UK, Sweden, UK, UK, Europe

7, the following moment is axisymmetric graphics for (a)

A, B, C, D,

8. If the note with the word "B" is facing the mirror, (B,) will appear in the mirror.

A, B, C, D,

9. The point that is symmetrical with point P (-3,2) about Y axis is (C.)

A.(3，2)b .(3，2) C. (3，-2)d .(3，-2)

10. The reading of the electronic meter that Xiao Qiang saw in the mirror is as shown in the figure, so the actual reading of the electronic meter is10; 5 1 .

4. Drawing questions.

Draw the symmetry axis of the picture below.

5. Answer the questions.

1. Determine whether the following figure (as shown in figure 14-6) is axisymmetric. (2, 3, 4, 5)

2. Judge whether the following figure (as shown in figure 14-7) is symmetrical about a straight line. (1 asymmetric)

3. As shown in figure 14-8, they are all symmetrical figures. Please observe and point out which figures are axisymmetric and which figures form axisymmetric.

Axisymmetric graphs: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10.

4. Two circles with different sizes can form five graphs as shown in figure 14- 12. Please find the symmetry axis of each figure and tell me what the characteristics of their symmetry axes are.

5、(2003? Jilin) In figure 14- 17, which one is different from the other three in terms of the properties of geometric figures? Please point out this figure and briefly explain your reasons.

A: Figure 2; The reason is that it is not an axisymmetric figure, and everything else is axisymmetric.

6. Find the area of the shaded part on the right. (Unit: cm)

What is actually sought is the area of two circles.

S=2лr2

=2×3. 14×4

=25. 12