Write the equations of two lines that intersect at the point A(3,1-1) and are perpendicular.

Not enough information was provided so I just used point A as the point on both of my lines : [x,y,z]= [3,1,-1]+t[1,-3,4] and [x,y,z]=[3,1,-1]+[3,1,0]. For the direction vectors I arbitrarily chose points that would yield 0 when I applied the dot product.

I'm not sure if this is correct.