Question

Let u = <5, 6>, v = <-2, -6>. Find -2u + 5v.

<-20, -42>

<-20, 0>

<0, 18>

<-6, 0>

Answer 1

Do you have any ideas?

Answer 2

I originally put C and got it wrong so no :/

Answer 3

Did you type your options rightly? or is A supposed to be -20, -24?

Answer 4

to find -2u you would multiply everything in vector u by -2

so what is the vector -2u equal to?

Answer 5

No i copied it straight from the test.. and
-2(5(-2)) ? irdk

Answer 6

u = <5, 6>

-2*u = -2*<5, 6>

-2*u = <-2*5, -2*6> ... notice how I'm multiplying everything by -2

-2u = <-10, -12>

Answer 7

do the same for 5v

then add up -2u and 5v

Answer 8

Yeah so then
5v would equal
v= <-2,-6>
5*v= 5*<-2,-6>
5*v=<5*(-2)5*(-6)>
5*v= <-10,-30>

Answer 9

right?

Answer 10

correct

Answer 11

to add vectors, you just add the corresponding components

Answer 12

example

<3,7> + <-2, 6> = <3+(-2), 7+6> = <1, 13>

Answer 13

so i would add
<-10, -12>+<-10,-30> ??

Answer 14

yes

Answer 15

so how would i do that ? -10+(-10) and -12+(-30) ?

Answer 16

yes add up the individual components

Answer 17

<-20,-42>

Answer 18

correct. That's your final answer

Answer 19

omg your a life saver.. wanna help me on some more?