I've tried almost everything with this question, but
I can't figure it out. I really need help solving it. Can you also tell me how you solved it? There are more just like it.

Question

I've tried almost everything with this question, but 
I can't figure it out. I really need help solving it. Can you also tell me how you solved it? There are more just like it.

cbreadbox · Answer

attachment

jim_thompson5910 · Answer

if vector u = <3,5> then what is vector -4*u equal to?

cbreadbox · Answer

-23.3236?

jim_thompson5910 · Answer

I don't know how you're getting that. You just multiply each coordinate by -4 u = <3,5> -4*u = -4*<3,5> -4*u = <-4*3,-4*5> -4*u = <-12,-20> make sense?

cbreadbox · Answer

oh. makes sense. what do I do next? 
(-12, -20) *(-8, 8)

jim_thompson5910 · Answer

now we dot product those vectors together

the dot product is where we multiply the corresponding coordinates and then add up the products

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