How to find the magnitude of a vector given direction and degrees?

Question

can someone help me..

i'm in a big problem now...

im stuck at this question..

can someone help me?

Vector A has magnitude 188 units pointing 30.0 degrees North of West. Vector B points 50.0 degrees East of North & Vector C points 20.0 degrees West of South. These three vectors add to give a resultant vector that is zero. Find the magnitudes of Vector B and C.

THANX in ADVANCE!!!

Answer 1

You can find this graphically

draw a vector diagram with Vector A (to scale) representing 188 at an angle of 150 degrees (30 degrees north of west) from a selected zero point on the page.

Vectors B and C form a value of the exact reverse of this

so draw a line 188 at angle 330 degrees (30 degrees south of east) representing the sum of vectors B and C. Call this Vector -A

Now draw another  line from the zero point, 200 long at an angle of 40 degrees. The length doesn't matter yet This will be Vector B when we are finished

Draw another line from the OUTER END of Vector -A,  200 long at an angle of 70 degrees (20 degrees east of north). This is the reverse of Vector C

Extend this line and the line representing Vector B until they meet

Measure their lengths

Now you can draw Vector C from the zero point at an angle of 250 degrees (20 degrees west of south) and another line from the OUTER END of Vector -A to complete your parallelogram for Vector (B+C)

Vector B is 370 units Vector C is 353 units