Given the following equations in the given interval 0 < x < 360

1 + tan^2x = 3tanx

i got x = -2.6 and x = -0.4

since the answers are negative, shudnt i use the 2nd and 4th quadrant to ge to get the answes? The answers at the back of the book use the 1st and 3rd quadrant. Have i gone wrong??????