X/5-g=a for x ,solve . can someone solve as well as explain the process of these equations

1. are the triangles similar and if so why? what is the value of x? show your work.

Solve for x and select the correct answer

The perimeter of an equilateral triangle is 4 cm more than the perimeter of a square and the length of a side of the triangle is 8 cm more than the length of a side of the aware. find the length of a side of the equilateral triangle