Consider two lines `L_1a n dL_2` given by `a_1x+b_1y+c_1=0a n da_2x+b_2y+c_2=0 respectively where c1 and c2 !=0,` intersecting at point `PdotA` line `L_3` is drawn through the origin meeting the lines `L_1a n dL_2` at `Aa n dB ,` respectively, such that `PA=P B` . Similarly, one more line `L_4` is drawn through the origin meeting the lines `L_1a n dL_2` at `A_1a n dB_2,` respectively, such that `P A_1=P B_1dot` Obtain the combined equation of lines `L_3a n dL_4dot`