
Example: If xy = 3 and xy = 10, find the value of x^{2}+y^{2}. Solution: Given that, xy = 3 Squaring on both sides, we get (xy)^{2} = 3^{2} x^{2}+y^{2}2xy = 9 x^{2}+y^{2}2.10 = 9 (Since xy = 10) x^{2}+y^{2}20 = 9 x^{2}+y^{2} = 9+20 x^{2}+y^{2} = 29. Directions: Solve the following problems. Also write at least ten examples of your own. 