Mathematics - Straight Lines Question with Solution | TestHub

For concurrency of 3 lines the determinant of coefficients of equations should be 0 . i.e. $\left|\begin{array}{ccc}3& -4& -13\\ 8& -11& -33\\ 2& -3& \lambda \end{array}\right|=0$ $\Rightarrow 3(-11\lambda -99)+4(8\lambda +66)-13(-24+22)=0$ $\Rightarrow -33\lambda -297+32\lambda +264+312-286=0$ $\Rightarrow -\lambda -583+576=0\Rightarrow \lambda =-7$