Question

5. If the area of an equilateral triangle is 36/3 cm’, find its perimeter
.
6. If the area of an equilateral triangle is 81 73 cm’, find its height.
7 Fach side of an equilateral triangle measures 8 cm. Find (i) the area​

Answer 1

Step-by-step explanation:

Area of equilateral triangle =

4

3

(side)

2

∴

4

3

(side)

2

=36

3

(side)

2

=36×4

=9×4×4

=(4×3)

2

side=12cm

perimeter =3×side

=3×12

=36cm hope it helps please mark as brainlliest

Answer 2

Answer:

Step-by-step explanation:

5.The area of an equilateral triangle is 36√3cm2. Its perimeter is. Solution : √34×a2=36√3⇒a2=144⇒a=12

6.√3/4 × a² = 81√3

=> a² = (81√3 × 4)/√3

=> a² = 324

=> a = √324

=> a = 18 cm

Then,

-----------

Height = √3/2 × a = (√3/2 × 18) cm = 9√3 cm

HOPE IT HELPS

7.According to the Heron's formula, Area (A) of the triangle having sides a,b,c units is  

A=  

s(s−a)(s−b)(s−c)

​  

 

where

s=  

2

a+b+c

​  

 

For the given triangle,

a=b=c=8cm

s=  

2

8+8+8

​  

=12

A=  

12(12−8)(12−8)(12−8)

​  

 

A=  

3×4×4  

3

 

​  

 

=4×4  

3

​  

 

=16  

3

​  

 

Area of the triangle =  

2

1

​  

×base×altitude=16  

3

​  

 

2

1

​  

×8× altitude=16  

3

​  

 

Altitude =  

4

16  

3

​  

 

​  

=4  

3

​mark as brainlist