find net force of ring?

Question

Find net force on the ring..?
There are four forces acting on a ring.
Force A is 20 lbs at an angle of 20 degree relative to the horizontal.
Force B is 20 lbs at an angle of 50 degrees relative to the horizontal.
Force C is 15 lbs at an angle of 30 degrees below the horizontal.
Force D is 30 lbs at an angle of 70 degrees below the horizontal.
What is the net force on the ring?
Image kinda looks like this:
http://i76.photobucket.com/albums/j4/pxg...

Answer 1

In general

Fx= F cos(angle)
Fy= F sin(angle)

Obtain the resultant Frx as a sum the x components algebraically (pay attention to direction (sines))
Obtain the resultant Fry as a sum the y components algebraically

The resultant Fr=sqrt(Frx^2 + Fry^2)
and the resulting angle is
Ar= arcTan(Fry/Frx)

Have fun