Hi dear friends...
1- Draw an equilateral triangle ABC.
2- Make two points on each side to get (ABC+6point= 9 points), with 4 points on each side.
3- Give the numbers( 1 to 9 ) to these points, so that the sum of 4 numbers on each side is the same.
A+point1+point2+B= B+point3+point4+C= C+point5+point6+A