Draw isosceles Triangle

The triangle is a closed geometric shape that contains three sides. There are several types of triangles in the geometry world. We can divide the triangles according to their angles and sides. We can define the isosceles triangle by using its sides.

      The triangle that has two equal or congruent sides in its measure is called as isosceles triangle. We can say that the equilateral triangle is also as an isosceles triangle,since the equilateral triangle has three equal sides . while we draw a isoscles triangle we have to see that two sides triangle must be equal.

draw Isosceles Triangle:

• when we draw a isoceles triangle, angles are congruent i.e., an angles of each sides are equal.
• when we draw a isoceles triangle diagonals of an isosceles triangle must be congruent.
• The measurement of the adjacent angles is giving the 180 degree. x = y = 180^o

Formulas for Isosceles triangle:

• Hight,  h = √(b² - `(1/4)` a²)
• Perimeter of Isosceles Triangle = A + B + C
• Area of isosceles triangle A = (b* h)/2

Example problems:

1) Find the area of isosceles triangle with the base and height are 5 cm and 7 cm.

solution:

We can find the area of given problem using the following formula:

Area A= (b*h)/2

Substitute the values of b and h into the above formula. Then we get,

         A= (5*7)/2

 Here multiplying to the values of 5 and 6 then dividing by 2.

  Then we get the final solution.   

 Answer A=17.5 cm²

2) Find the perimeter of Isosceles triangle that has side, Side 1 =10 cm, Side 2 = 10, Side 3 = 7 cm.

Solution:

   Given, Side 1 =10 cm, Side 2 = 10, Side 3 = 7 cm.

  Perimeter of Isosceles triangle   = Side 1+ Side 2+ Side 3

                                                         = 10 + 10 + 7

  Perimeter of Isosceles triangle  = 27 cm

3) Find the height of the isosceles triangle of the base a = 7 cm and equal sides b = 11 cm.

Solution:

The height of the isosceles triangle is given by the formula:

             h = √(b² - `(1/4)` a²)

substitute the a = 7cm and b = 11 cm. in the formula,

             h = √(11² - (1/4)*7² )

             h = √(121 - `(49/4)` )

             h = √(121 - 12.25 )

             h = √(108.75) = 10.428 ≈ 10.4 cm

Height of the isosceles triangle = 10.4 cm