Two consecutive sides of a parallelogram are 4x+5y=0 and 7x+2y=0 . If the equation  of one diagonal is 11x+7y=9 , then the equation to the other diagonal is

Given equations are 4x+5y=0…… (i) 7x+2y=0…… (ii) 11x+7y=9…… (iii)  Solving (i) and (iii) A≡53,−43 Solving (ii) and (iii) C≡−23,73M= midpoint of AC=53−232,−43+732=12,12 Equation of  diagonal OB is y−y1=y2−y1x2−x1x−x1⇒y−0=12−012−0(x−0)⇒x−y=0Therefore, the correct answer is (3).