AP Physics
posted by Paige .
Consider the vectors A = 2.00 i + 7.00 j and B = 3.00 i  2.00 j.
(a) Sketch the vector sum C = A + B and the vector subtraction D = A  B.
(b) Find analytical solutions for C and D first in terms of unit vectors and then in terms of polar coordinates, with angles measured with respect to the positive x axis.
I just can't figure out what the degree should be for the D vector polar coordinate

D=i+9j
angle of D= arctan 9 
A+B = (2+3)i + (72)j = 5i+5j
AB = i+9j
just draw a triangle with hypotenuse from (0,0) to (1,9)
tanθ = 9/1
θ = 180+83.66° = 263.66° or 96.34° 
Oops. That would be
18083.66 = 96.34° 
thank you! the answer was 96.3