Hello!
The answer is: [tex]a.b=15[/tex]
Why?
It's a scalar product of vectors. The scalar product gives as result a or scalar number.
The scalar product consists in multiplying the axis components each other (x-component by x-component and so) and them performing an algebraic sum.
So, the scalar product of the given vectors will be:
[tex]a.b=ax*bx+ay*by=9*5+(-6*5)=45-30=15[/tex]
Have a nice day!
