Question

The perimeter of an equilateral triangle 60m. Find its area and altitude

Answer 1

hello friend : - ) 
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According your question we need to find out the area of equilateral triangle :-)

follow my steps what i am doing as we know that :- ) 

there are 3 sides of triangle specially in equilateral triangle all sides length 

same :-) 

so perimeter of equilateral triangle = > x+x+x=>3x

and given perimeter of equilateral triangle is 60m so we will now equate the 

equation   as   60 m= > 3x   and here we got x= > 20 m now see the picture i 

have made for you in paint :-) 

As you see that AB and AC are the hypotenuse sides , BD and DC are the  

base  and AD is the altitude so here we can find the altitude AD using  

pythagoras  theorem as  AD = > √ AC² - BC²  

AD = > √400-100 = >√300 => 10√3 

we got the altitude of triangle which equals to 10√3 

now here are two equal triangle i will just find the area of one triangle then 

double the area to calculate the area of equilateral triangle 

as area of triangle => 1/2  × base ×altitude ×2 which means 

1/2 × 10 × 10√3×2 = > 100 √3 is the area  of the triangle 

HOPE THIS HELPS YOU 
@ engineer gopal !