Question

find the area of a triangle whose sides are 20cm 21 cm 29

Answer 1

Answer:

here we use heron's formula  

area=

\sqrt{p(p - a)(p - b)(p - c)}  

where a,b,c are the sides of triangle

here we need to find p which is equal to  

\frac{a + b + c}{2}  

p=35

Therefore area of triangle=√35(35-20)(35-21)(35-29)=√35×15×14×6=√44100=210

Answer 2

Hey Mate,

Given,

a = 20 cm

b = 21 cm

c = 29 cm

Perimeter = a + b + c = 20 + 21 + 29 = 70 cm

Since, all three sides are given, we will use Heron's formula to find the area of the triangle.

Heron's Formula :-

$\sqrt{(s)*(s-a)*(s-b)*(s-c)}$ ( Where, s = semiperimeter or perimeter / 2  and a, b and c are the sides of the triangle )

Area of the Triangle = $\sqrt{(35)*(35-20)*(35-21)*(35-29)}$

Area of the Triangle = $\sqrt{35*15*14*6}$

Area of the Triangle = $\sqrt{44100}$

Area of the Triangle = 210 sq. cm

Therefore, the area of a triangle whose sides are 20 cm, 21 cm and 29 cm is 210 sq. cm.

Hope it Helps!