The perimeter of the square is 2.25x and the equilateral triangle is 1.5x + 6. What is the value of x?

x = 4

Step-by-step explanation:

2.25x=1.5x+6

divide on both sides by 1.5x which equals

1.5x=6

divide both sides by 1.5

x=4

A regular star is equilateral and has congruent angles at the vertices and congruent angles at each indentation. 
Equilateral means all sides are equal. The star is equiangular too since it has the same measure of angles. 

The number of lines of symmetry of the said regular star can be explained through the reflection symmetry, also known as Mirror symmetry whereby the star's half is the reflection of the other half of the same star.