To get the best deal on Tutoring, call 1-855-666-7440 (Toll Free)

Isosceles Triangle Calculator

Isosceles Triangle Calculator is an online tool to calculate perimeter and area of isosceles triangle. Here it can calculate area only if height is given. Isosceles Triangle Calculator is a tool which makes calculations easy and fun. For calculating perimeter it is necessary that measures of base and equal side should be given, but for calculating area height is also needed.

Steps for Isosceles Triangle

Back to Top
Step 1 :  

Take the equal sides of an isosceles triangle as "a" and base as "b". Height can be taken as "h" if given in the question, else, it can be found by Pythagorean theorem.

Step 2 :  

Apply the formula for Area of an Isosceles triangle =$\frac{1}{2}$×b×h

Step 3 :  

For perimeter, apply the formula P = 2×a + b

Example problems on Isosceles Triangle

Back to Top
  1. Find the area of an isosceles triangle having equal sides 10cm and base 16cm.

    Step 1 :  


    a = 10cm b = 16cm and h = √(a2 - (b/2)2 = √(100 - (b/2)2 = √(100 - 64) h = 6cm

    Step 2 :  

    Apply formula for area of an Isosceles triangle = $\frac{1}{2}$×b×h.

    Area of an Isosceles triangle= $\frac{1}{2}$×16×6.

    Area of an Isosceles triangle= 48cm2

    Answer  :  

    Area = 48cm2
    Perimeter = 36cm

*AP and SAT are registered trademarks of the College Board.