vector question: In the sum A + B = C, vector A has....

[soccerball3211]

In the sum A + B =C, vector A has a magnitude of 12.4 m and is angled 42.1° counterclockwise from the +x direction, and vector C has a magnitude of 14.2 m and is angled 19.4° 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.

Can Someone tell me why my answers are incorrect?

For part A I calculated 5.52 m and for part B I calculated 234.8 degrees.

 

[skeeter]

try again ...

if A + B = C, then B = C - A

B_x = C_x - A_x
B_x = 14.2cos(199.4) - 12.4cos(42.1)

B_y = C_y - A_y
B_y = 14.2sin(199.4) - 12.4sin(42.1)

 

[soccerball3211]

I calculated 26.1m at 210 degrees.

 

[soroban]

Hello, soccerball3211!

I calculated 26.1m at 210 degrees.

Right . . . ya done good!