Which figure has exactly five lines of symmetry? a. regular hexagon b. square c. regular pentagon d. equilateral triangle

D has three lines of symmetry.

C has 5 lines of symmetry

B has 4 lines of symmetry

A has 6 lines of symmetry.

Remark

The two diagrams below show two shapes.

1. The one on the right, shows how a regular pentagon could have 5 lines of symmetry. Notice how one of them comes from the vertex to the middle of the side opposite.

2. the square was put in just so you could see what a line of symmetry is. The diagonal shows that you could fold one opposite corner to the other creating one of two lines of symmetry and the other line goes across the middle of of one side of the square to the middle of the other side.

(sin 42)/31. = sinx)/37

sinx = 37 (sin42)/31

= 37× 0.66/31 = 0.787

x= 51.9

other angle opposite to y = 180-51.9-42

= 180- 93.9 =86.1

so

sin42)/31 = sin 86.1)/y

0.021 = 0.997 /y

y= 0.997/0.021 =47.47