Determine the Angle $\theta$ Through Which the Axes Are Rotated $5 x ^ { 2 } - 4 x y + 6 y ^ { 2 } = 9$

Multiple Choice

Determine the angle $\theta$ through which the axes are rotated.Round your answer to two decimal places. $5 x ^ { 2 } - 4 x y + 6 y ^ { 2 } = 9$

A) $\theta = 79.87 ^ { \circ }$
B) $\theta = 77.87 ^ { \circ }$
C) $\theta = 81.87 ^ { \circ }$
D) $\theta = 80.87 ^ { \circ }$
E) $\theta = 78.87 ^ { \circ }$