Posted by Sophie on .
For 4x^2  4xy + y^2 = 4 find θ, the angle of rotation about the origin, to the nearest degree?
a) 27°
b) 63°
c) 333°
d) 307°
I got A, is this right?

Math 
Reiny,
I had 26.6 or 333.4 in a positive direction
tan 2θ = B/(AC)
= 4/(41) = 4/3
2θ = 53.13
θ = 26.13 
Math 
Sophie,
oh, so it is C?

Math 
Reiny,
has to be
didn't you also get 26.6 degrees?
that is not given.
What angle is coterminal with 26.6 ?
It is 333.4 . 
Math 
Reiny,
Here is a webpage that has your type of question
http://education.yahoo.com/homework_help/math_help/problem?id=miniprecalcgt_8_1_1_26_70
press "STEP" to go through the problem.
Notice they leave their angle as a negative. 
Math 
Sophie,
oohh yes i did! thanks!!