Question

factorise the following
9(x+y)²-x²

Answer 1

Step-by-step explanation:

$9 {(x + y)}^{2} - {x}^{2} \\ 9( {x}^{2} + {y}^{2} + 2xy) - {x}^{2} \\ 8{x}^{2} + 9 {y}^{2} + 18xy \\ here \\ a = 8 \\ b = 18y \\ c = 9 {y}^{2} \\ \\ \frac{ - b + \: or \: - \sqrt{ {b}^{2} - 4ac } }{2a} = x \\ x = \frac{ - 18y + \: or \: - \sqrt{324 {y}^{2} - 288 {y}^{2} } }{16} \\ 16x = - 18y + \: or \: - 6y \\ 16x = - 12y \: \: \: \: \: \: \: \: \: \: or \: \: \: \: \: \: \: 16x = - 24y \\ 16x + 12y = 0 \: \: \: \: \: or \: \: \: \: \: \: \: \: 16x + 24y = 0$