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andrecoelho
Let B = 5.50 m at 60º. Let C have the same magnitude as A and a direction angle greater than that of A by 25º. Let A•B = 27.6 m^2 and B•C = 33.9 m^2. Find the magnitude and direction of A.
so i am considering the horizontal as the refrence.. lets say A makes an angle theta with the horizontal.. then the angle made by A with B is theta - 60 (or 60 - theta. doesn't matter) A.B= 27.6 there fore\[ABcos( \theta - 60) = 27.6 ----------(1)\] C has the same mangnitude as A and makes angle with horizontal 25 + theta B.C= 33.9.. so similary build the second equation .. since B value is known to you.. you ll have two equations in 2 variables (A and theta).. solve it