Isosceles triangle is defined as a triangle consisting of two equal sides and equilateral triangle is defined as a triangle which consists of three equal sides. Triangle consists of an Altitude and a base we must know how to construct an altitude of a triangle. For this let us consider the following steps for the construction of altitude in a triangle. Firstly, extend the base of triangle on which altitude is to be drawn.

Take the compass and keep the compass on the end Point of base take a measure more than half in the compass. Then, draw an arc at upper part of base and at the lower space of base with same measure taken on compass and then keep the compass at other end and again follow the same procedure of marking the arcs. Now, two points are obtained at the upper and lower space of base by the Intersection of arcs form both ends. Join these two points and a straight line is obtained passing through base of triangle and also perpendicular to it. Now, this line so obtained is defined as altitude of triangle and it will be perpendicular to base of triangle that is it will be forming an angle of 90 degree from the base.