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.
Use isosceles and equilateral triangles. Using the Base Angles Theorem. A triangle is isosceles when it has at least two congruent. sides. When an isosceles triangle has exactly two congruent. sides, these two sides are the legs. The angle formed by the. legs is the vertex angle. The third side is the base of the. isosceles triangle.