I had my math finals today, and one question was that i had to use the Law of cosines i think its called, It was a triangle. AC=650m and BC=

Law of Cosines:  c²  =  a² + b² -2abcos(C)

For this problem:  c = AB     a  =  BC = 700     b = AC = 650

--->                  c²  =  700² + 650² - 2(700)(650)cos(121.1°)

--->                  c²  =  1382545

--->                    c  =  1176.