Suppose ABC is an equilateral triangle and P is a point inside the triangle, such that PA = 3 cms., PB = 4 cms., and PC = 5 cms.
Then find the length of the side of the equilateral triangle.
ive noticed that they all used cosine law in solving this problem. In more elementary way we could solve that by plotting the vertices to the trinagle in a cartesian plain which has the coordinates of (0,0),(s/2,s3/2),(s,0). Then use the formula for obtaining the distance between two points and you will get three equations and three unknowns then manipulate it and you will get the value of s=6.76643 cm

Posted by joel
on 20040102 22:37:33 