Calculator Use

Enter a, b, A, B and click Calculate to get the values of the isosceles triangle.

What is isosceles triangle?

An isosceles triangle is a triangle with two sides of equal length, which are called legs. The third side of the triangle is called base. Vertex angle is the angle between the legs and the angles with the base as one of their sides are called the base angles.

What is the Types of Isosceles Triangle?

Isosceles acute triangle

Isosceles right triangle

Isosceles obtuse triangle

What is the Properties of Isosceles Triangle?

As the two sides are equal in this triangle, the unequal side is called the base of the triangle

The angles opposite to the two equal sides of the triangle are always equal

The altitude of an isosceles triangle is measured from the base to the vertex (topmost) of the triangle

A right isosceles triangle has a third angle of 90 degrees

What is the Altitude of an Isosceles Triangle?

Given two sides of equal length a and base b calculate Altitude of base b (h_b) in an Isosceles triangle

Altitude of an isosceles triangle is given as:

h_b = √(a² - b²/4)

Given two sides of equal length a and base b calculate Altitude of side a (h_a) in an Isosceles triangle

h_a = 2 A/a = 2 b h_b / 2a = b h_b / a = (b/a) · √(a² - b²/4)

where a is two sides of equal length of the Isosceles triangle, and b is a base, h_b is the Altitude of base b

How to calculate the Area of an Isosceles triangle?

Given base b and Altitude of base b (h_b) calculate the Area A(Given b, h_b calculate A)

A = b · h_b/2

Given two sides of equal length a and base b calculate the Area A(Given a, b calculate A)

A = b · h_b/2 = 1/2 · b · √(a² - b²/4)

What are the formulas and calculations for an isosceles triangle?

Area(K)	K2 = b2 * (4 × a2 - b2) / 16, K = (b/4) * √(4a2 - b2)
Perimeter (p)	2 × a + b
Angle bisector of B ( tb )	tb2 = 4 × a2 - b2 / 2
Angle bisector of A( ta )	ta2 = b2 × a × (2a + b) / (a + b)2
Median of Leg ( ma )	ma2 = (2 * b2 + a2) / 4
Median of Base ( mb )	mb2 = (4 * a2 - b2) / 4
Circumscribed Circle Radius(Circumradius)	a / ( 2 * sin (A)) or b / ( 2 * sin (B))
Inscribed Circle Radius(Inradius) (r)	r2 = b2 × (2a - b) / (4 × (2a + b))
Height from Base Angle(ha)	(b/2a) * √(4a2 - b2)
Height from Apex (hb)	(1/2) * √(4a2 - b2)