SOLUTION: can you please help me solve(((What is the area of an equilateral triangle with perimeter 12? )))

Algebra.Com
Question 200996This question is from textbook geometry
: can you please help me solve(((What is the area of an equilateral triangle with perimeter 12? ))) This question is from textbook geometry

Found 2 solutions by rfer, RAY100:
Answer by rfer(16322)   (Show Source): You can put this solution on YOUR website!
a^2+b^2=c^2 for a right triangle to find the heigth
2^2+b^2=4^2
b^2=16-4=12
b=3.46
a=lh
a=1/2*4*3.46=6.92 sq something

Answer by RAY100(1637)   (Show Source): You can put this solution on YOUR website!
Remember,, equilateral triangle,, sides same,,,,
.
Perimeter = sum of sides = s+s+s = 3s =12,,,,s=4
.
With s=3, we could use Herons Formula ,, but just as easy to resolve.
.
Area = 1/2 * base * height
.
Height is perpendicular to base, therefore c^2 = a^2 + b^2.( use rough sketch)
.
in our case,,,c= 4,,,,a=2,,,,therefore c= 3.46,,,which is height
.
Area = 1/2 * 4 * 3.46 = 6.93
.
Check,,,rough sketch shown height to vertex makes a 30-60-90 triangle, with sides 1 - 2 - sqrt3,,
with leg 2 and hypotenuse 4, therefore other leg is 2(sqrt3) {height},
and area is 1/2 * 4* 2sqrt3 = 4 sqrt3 = 6.93,,,ok
.

RELATED QUESTIONS

can you please help me solve ((( What is the area of an equilateral triangle with... (answered by solver91311)
find the area of an equilateral triangle with a perimeter of 54 cm. can you help me... (answered by math_helper)
Can you show me the equation to the solution of this problem: An equilateral triangle... (answered by meetkisai)
The perimeter of an equilateral triangle is 12 feet. what is the... (answered by rfer,reviewermath)
Good day! Can you help me with my homework? Here's the question An equilateral... (answered by stanbon)
can you please help me solve ((( What is the area of a circle with diameter 12?... (answered by nerdybill)
An equilateral triangle has an area of 300square root of 3. Find the apothem. My... (answered by Earlsdon)
what is the perimeter and area of an equilateral triangle with side length 4 feet (answered by edjones)
Which measure is closest to the area of an equilateral triangle with a perimeter of 12... (answered by CubeyThePenguin)