ANSWER
[tex]<8,4> \bullet< - 3,5> = - 4[/tex]
EXPLANATION
The dot product of two vectors:
[tex] < a,b > [/tex]
and
[tex]< c,d> [/tex]
is
[tex] < a,b > \bullet< c,d> = ac + bd[/tex]
The given vectors are:
[tex]<8,4> [/tex]
and
[tex]< - 3,5> [/tex]
The dot product of these vectors is
[tex]<8,4> \bullet< - 3,5> = 8 \times - 3 + 4 \times 5[/tex]
[tex]<8,4> \bullet< - 3,5> = - 24 + 20[/tex]
[tex]<8,4> \bullet< - 3,5> = - 4[/tex]
