MathematicsEasy249×since 2002Q2480The two lines x=ay+b,z=cy+d;x=ay+b, z=cy+d;x=ay+b,z=cy+d; and x=a′y+b′,x=a'y+b' ,x=a′y+b′, z=c′y+d′z=c'y+d'z=c′y+d′ are perpendicular to each other if :Aaa′+cc′=−1aa'+cc'=-1aa′+cc′=−1Baa′+cc′=1aa'+cc'=1aa′+cc′=1Caa′+cc′=−1{a \over {a'}} + {c \over {c'}} = - 1a′a+c′c=−1Daa′+cc′=1{a \over {a'}} + {c \over {c'}} = 1a′a+c′c=1Check answerSkip