The book deals with the generalizations of Pythagoras theorem to polygons. The celebrated result of the Pythagoras theorem representing the sum of squares of two (positive) integers as the square of another integer has been extended to quadrilaterals composed of two right triangles so that the sum of squares of its first three sides equals the square of the remaining side. In the language of algebra, integral solutions of a quadratic equation a2 + b2 + c2 = d2 are explored. The first 18 Sections in the first chapter deal with the special cases when the length of the fourth side exceeds that of the third side by numeric values: 1-17. The last section consists of some miscellaneous results. For more details, please visit https://centralwestpublishing.com