Two forces with magnitudes of 200 and 100 pounds act on an object at angles of 60° and 170° respectively. find the direction and magnitude of the resultant force. round to two decimal places in all intermediate steps and in your final answer.

We can find equals to the given components

Then you have to find equal for  f2= 100cos(170) ,100sin(170) which is 
Substract the vectors to find F3 coordinates 
With theese new coordinates it is possible to find the direction and magnitude by using arc tan and square rooting. You should make   and plug it to the arc tan function tan-. You will obtain direction 89.54, then find magnitude of the square root of 36315.4 --

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