Answer:
(a) Orthogonal, (b) Neither, (c) Parallel, d( Orthogonal
Step-by-step explanation:
a and b are parallel is a=kb
a and b if a dot b = 0
(a) a dot b = (9)(-4)+6(6)=-36+36=0
a and b are orthogonal
(b) a dot b = 40-7-21=12
a=kb -> there is no k value satisfying the equation
a and b are neither parallel or orthogonal
(c) a dot b = -12-108-48=-168
a=kb -> k=-3/4 satisfies the equation
a and b are parallel
(d) a dot b= 9-3-6=0
a and b are orthogonal
