If x^2 – y^2 = 7 and x – y = 1, then the length of a diagonal of a rectangle with length and width respectively x cm and y cm will be

If the length of a rectangle is increased by 1/3rd and the width is decreased by 1/3rd, then the area of the rectangle is decreased by the fraction

The length of a rectangle is 1 cm more than its width and its perimeter is 14 cm, then the area of the rectangle is

X, Y and Z are three equilateral triangles. The sum of the areas of X and Y is equal to the area of Z. If the side lengths of X and Y are 6 cm and 8 cm respectively, then what is the side length of Z?

The length and breadth of a square are increased by 30% and 20% respectively. The area of rectangle so formed exceeds the area of the square by :

ABC is a triangle with sides AB = 41 cm, BC = 28 cm and CA = 15 cm. If D, E and F are the mid-points of AB, BC and CA respectively, then what is the area of the triangle DEF?