Question

The dot or scalar product of two (3d) vec- tors ⃗a = ⟨a1,a2,a3⟩ and ⃗b = ⟨b1,b2,b3⟩ is defined as

Answer 1

Yes, yes, we know all of that.  It certainly took you long enough to
get around to asking your question.

If
     a = (14, 10.5, 0)
and
     b = (4.62, 9.45, 0) ,

then, to begin with, neither vector has a z-component, and they
 both lie in the x-y plane.

Their dot-product  a · b = (14 x 4.62) + (10.5 x 9.45) =

                                             (64.68)   +   (99.225)  =  163.905 (scalar)          


I feel I earned your generous 5 points just reading your treatise and
finding your question (in the last line).  I shall cherish every one of them.