Answer:
Step-by-step explanation:
Cos θ =<u> u*v </u>
IuI *IvI
u * v = 7*(-1) + (-2)*2
= -7 - 4
= -11
IuI = 
= 
= 
I vI = 
= 
= 
Cos θ = 
= 
Cos θ = -0.68
θ = 132.5°
Answer:
Answer D is correct.

Step-by-step explanation:

Answer:
yes your eqation is correct...