If and cm, determine the perimeter of .
In the figure, bisects in . The bisector of an interior angle of a triangle divides the opposite side of the triangle into two parts. The ratio of the lengths of these parts is equal to the ratio of the lengths of the other two sides of the triangle.
Since , the length of is . To find the length of in terms of , use Pythagoras as follows:
Now solve for .
Since , the length of is , and the length of is . Thus, the perimeter of is .