The solution of pair of linear equations Px + qy = 2P and qx + Py = 2q, (P2 – q2 ≠ 0) is equal to रैखिक समीकरणों के युग्म Px + qy = 2P व qx + Py = 2q, (P2 – q2 ≠ 0) का हल है
Three lines px+qy+r=0,qx+ry+p=0 and rx+py+q=0 are concurrent, if