Please help!!

Two forces with magnitudes of 120 and 70 pounds act on an object at angles of 60 degrees and 150 degrees, respectively. Find the direction and magnitude of the resultant force. Round to two decimal places in your final answer.

Respuesta :

resolving horizontally .  Make  forces to the right positive 
resultant force =  70cos30-60cos60 = 60.62-60 = 0.62 lbs

resolve vertically  
resultant force =   120 sin60 - 70 sin30 = 103.92 - 35 = 68.92   lbs in downward direction

magnitude of the ressultant forsse = sqrt(68.92^2 + 0.62^2) =  68.92 lbs

direction of the force =  tan-1 (0.62 / 68.82) = 0.52 degrees east of south or  
a bearing of 
90 - 0.52  =  89.48 degrees