Question

Evaluate the dot product of (8,4) and (-3,5)

Answer 1

-4

Explanation:

a p e x

Answer 2

`<8,4> \bullet< - 3,5> = - 4`

EXPLANATION

The dot product of two vectors:

`< a,b >`

and

`< c,d>`

is

`< a,b > \bullet< c,d> = ac + bd`

The given vectors are:

`<8,4>`

and

`< - 3,5>`

The dot product of these vectors is

`<8,4> \bullet< - 3,5> = 8 * - 3 + 4 * 5`

`<8,4> \bullet< - 3,5> = - 24 + 20`

`<8,4> \bullet< - 3,5> = - 4`