HOW DO YOu classify triangles based on the side lengths?

Answer 1

Triangles are not classified by the length of their sides, but by their shapes. A right triangle, for example, is a triangle which includes one 90o angle. This is true regardless of the size of the triangle; it could have sides a thousand miles long or a thousandth of an inch long and still be a right triangle, as long as it has that 90o angle. An equilateral triangle has three sides which are all of the same length. This is true, again, regardless of the size of the triangle. The three sides could all be a million miles long, or they could be microscopic, but if they are all the same length, then the triangle is equilateral.

It would be better to ask about classifying triangles by the relative lengths of their sides.

If all the sides are different lengths, we class it as a Scalene Triangle. (Note that all three angles also are different.)

If exactly two sides have the same length we call it an Isosceles triangle (Note that two of the angles also are the same size. And try to get the spelling right!!!)

If all three sides are the same length, we call it an Equilateral triangle. (If you like you could say that it is a special case of an isosceles triangle). All three angle are the same and they always are sixty degrees each.