Calculus
posted by Sarah on .
Determine the value of k, so that u = [3,7] and v = [16,k] are perpendicular.

they're parallel

it says determine the value of k so that u and v ARE perpendicular .... if it was parallel, i don't think it would ask me to find k....... unless it's a trick question ...

slope of u = 7/3
so slope of perpendicular to u = +3/7
so
3/7 = k/16
7 k = 48
k = 48/7 
or...
their dot product must be zero
(3)(16) + 7k = 0
7k = 48
k = 48/7 
thank you everyone