For fabric at least 10 cm wider than half the chest measurement, 2 lengths + 1 sleeve length + 100 cm. For fabric at least 10 cm wider than 1/4 chest measurement: 4 lengths + 1 sleeve length + 200 cm. These are rough estimates and should give you plenty of fabric for a basic shirt or blouse. Add more for gathering, design features like bias cuts, pleats, etc.
An isosceles triangle is a triangle with two congruent sides and congruent base angles. congruent means equal. No matter which direction the triangle's apex, or peak, points, it's an isosceles triangle if two of its sides are congruent.
Triangles can be classified according to the lengths of their sides: 1  An equilateral triangle has all sides the same length. An equilateral triangle is also a regular polygon with all angles measuring 60Â°. 2  An isosceles triangle has two sides of equal length. An isosceles triangle also has two angles of the same measure, namely the angles opposite to the two sides of the same length; this fact is the content of the isosceles triangle theorem, which was known by Euclid.