SOLUTION: the vector sum of a force of 12N and a force of 9N is 3N. the angle between them is

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Question 1092738: the vector sum of a force of 12N and a force of 9N is 3N. the angle between them is
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Use the first vector as the x direction of the coordinate system,
(12,0)+(9cos%28theta%29,9sin%28theta%29)=(3,0)
So,
12%2B9cos%28theta%29=3
0%2B9sin%28theta%29=0
So then,
cos%28theta%29=-1
sin%28theta%29=0
So,
theta=pi