The perimeter of triangle ABC = 15 cm. Given that AB = 7 cm and angle BAC = 60 degreez, find the lengths of AC and BC.
Anyone could give me some hint how to go with this ? Because all i know is that b+c=8 ..
The rule of cosines tells us that
$(8-b)^2=b^2+49-7b\cos(60^o)$