Oh, sorry- I see this has already been discussed (sorry to shoot first). anony: dennis is correct.

"...an equilateral triangle has three sides all the same length. An isosceles triangle doesn’t (the hypotenuse is longer)..."

Sorry, that's not correct, unless the isosceles triangle also just happens to be a RIGHT triangle (the hypotenuse is the side opposite of the right angle). An isosceles triangle is simply a triangle with two sides of the same length (an equilateral triangle is also an isosceles triangle, incidentally).