How many lines of symmetry are there in a regular decagon

In a regular decagon, there are 10 lines of symmetry.

Step-by-step explanation:

Line of symmetry divides a figure into two equal halves so that if you flip the half image over the line of symmetry , the figure will look unchanged.

A regular decagon has 10 vertices and 10 edges.

To draw line of symmetry :

1.Draw lines to meet the exactly opposite point [shown by red color in the picture attached with the answer].

∴ 10 vertices will form 5 lines of symmetry.

2.Draw lines from the mid points of all the edges to the midpoint of the exactly opposite edge [shown by blue color in the picture attached with the answer].

∴ 10 edges will form 5 lines of symmetry.

⇒Total lines of symmetry in a decagon =5+5= 10

To solve this problem you must apply the proccedure shown below:   1. you have the following expression given in the problem above:   x^2y^2+2√(x^3y^4)+xy√y  2. therefore, you have:   x^2y^2+2(x^3y^4)^1/2+xy(y)^1/2  3. by the exponents properties, you obtain:   x^2y^2+2x^3/2y^4/2+xy^3/2  x^2y^2+2x^3/2y^2+xy^3/2  therefore, as you can see, the answer is: x^2y^2+2x^3/2y^2+xy^3/2