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**Urgent! Question Problem! Please Help!**

1. Homework Statement [/b]

In the sum A-> + B-> = C->, A-> vector has a magnitude of 13.8 m and is angled 44.0° counterclockwise from the +x direction, and vector C-> has a magnitude of 16.8 m and is angled 18.8° counterclockwise from the -x direction. What are (a) the magnitude and (b) the angle (relative to +x) of B->? State your angle as a positive number.

2. Homework Equations [/b]

3. The Attempt at a Solution

I don't know if its right or not. :(

sin(44)13.8 = 9.58628 for A

sin(18.8)16.8 = 5.41406368 for C

cos(44)13.8=9.926889245 for A

cos(18.8)16.8=15.90370757 for C

that's the two components of A and C. since you're trying to find B

it's C - A = B.

in the x direction: 5.41406368 - 9.58628 = -4.172

in the y direction: 15.90370757 - 9.926889245 = 5.976

The magnitude is simply sqrt (x component^2 + y component^2) = 7.288

the angle relative to +x is tan^-1(x component/y component) = tan^-1(-4.172/5.976) = -34.9 degrees.