Question

The perimeter of an isosceles triangle is 20cm and it's unequal side is 5cm, then find its area.​

Answer 1

Answer:

Step-by-step explanation:

Let the equal sides be x

Perimeter is 20 cm

-> 2x+5 = 20

-> x = 7.5 cm

From the diagram, we get the simple equation in which on substituting the values we get area as

1/2 * 5 * $\sqrt{a^2-b^2/4}$

= 1/2 * 5 * $\sqrt{ 7.5*7.5-25/4$

= 1/2*5 * $\sqrt{50\\}$

=25/$\sqrt{2$ or 25$\sqrt{2$/2