Magnitude and Direction of Vector

[mikegraham532]

I am trying to complete the math problem below for finding magnitude and direction. She gave me the answer but I have to show my work.
I found the magnitude but I can't figure out the direction. Can someone please help me?

 

[skeeter]

note the direction is toward quadrant III

[MATH]\theta = 180^\circ + \tan^{-1}(1)[/MATH]

 

[AmandasMathHelp]

Yes so you found what tan of A is so like the above suggests you just need to find inverse tan then relocate that angle to the third quadrant by adding 180. Also make sure in your work that you aren't taking the square root of a negative number. When you square -4 you should get a positive number.