Math Is Fun Forum

The two basic triangle formulas are the area of a triangle and the perimeter of a triangle formula. These triangle formulas can be mathematically expressed as; Area of Theorem 2: When a triangle side is constructed, the exterior angle formed is equal to the sum of the interior opposite angles. Theorem 3: The base angles of an isosceles triangle are equivalent. Hence, the formula for the Perimeter of a Triangle when all sides are given is, P= a+b+c. Where, a, b, c indicates the sides of the triangle.In geometry, a base angle of a shape is an angle within a shape that contains the base of the shape as one of its sides. For example, consider the triangle shown. We see that the base side of the triangle is a side of angle B and a side of angle C. Therefore, angles B and C are the base angles of the triangle.