An isosceles triangle has sides A, B, and C, such that sides A and B have the same length. Side C has a length of 14 and the triangle has an area of 42 . What are the lengths of sides A and B?

1 Answer
Mar 17, 2016

A= sqrt(6^2+7^2) => A= 5sqrt(3) = B

Explanation:

Given: Area of an isosceles triangle, A_Delta =42; C = 14
Required: Length of sides A and B:
Solution: A_Delta = 1/2 C*h; C = 14; h= height
42=1/2 (14*h); h=6 Now the height forms a right angle triangle with hypotenuse of A and sides of h and C/2. So you can use the Pythagoras Theorem:
A^2= h^2+(C/2)^2 you know h and C/2=7 solve of A
A= sqrt(6^2+7^2) => A= 5sqrt(3) = B