Add up the sides.
Chat with our AI personalities
-- Measure or calculate the length of each of its 3 sides. -- Add the lengths of its 3 sides. -- The sum is the perimeter of the triangle.
Use two sides and Pythagoras's theorem to work out the third side. Then simply add the three sides.
I think you need at least one other piece of information. A length of a side? An angle? Is it a right angled triangle?
Using Pythagoras' theorem and the quadratic equation formula the sides of the triangle work out as 6.25 cm and 15 cm. Therefore the perimeter of the right angle triangle is: 6.25+15+16.25 = 37.5 cm
Use the cosine rule: a2 = b2+c2 - 2bc*cos A An isosceles triangle has two equal sides.